Precursor for positive electrode active material, positive electrode active material, positive electrode, lithium secondary battery, and method for manufacturing precursor for positive electrode active material

Abstract

The present invention relates to a precursor for a positive electrode active material, the precursor including a nickel-based hydroxide containing nickel in an amount of 50 mol% or more on the basis of the total amount of all metals, wherein the precursor has a pore area ratio (PAR) of 5% to 10%, a SPAN value of 0.58 or less as defined by equation 1 below, and a sphericity of 0.8 or greater. [Equation 1] SPAN = (D90-D10) / D50

Description

Precursor for positive electrode active material, positive electrode active material, positive electrode, lithium secondary battery and method for manufacturing a precursor for a positive electrode active material

[0001] Cross-citation with related applications

[0002] The present application claims the benefit of priority based on Korean Patent Application No. 10-2025-0027119 filed on February 28, 2025 and Korean Patent Application No. 10-2026-0037256 filed on February 27, 2026, and all contents disclosed in said Korean patent application documents are incorporated into this specification.

[0003] Technology field

[0004] The present invention relates to a precursor for a positive electrode active material, a positive electrode active material, a positive electrode, a lithium secondary battery, and a method for manufacturing a precursor for a positive electrode active material. More specifically, the invention relates to a precursor for a positive electrode active material, a positive electrode active material, a positive electrode, a lithium secondary battery, and a method for manufacturing a precursor for a positive electrode active material having excellent capacity characteristics and improved resistance and lifespan characteristics.

[0005]

[0006] With the recent rapid proliferation of battery-powered electronic devices such as mobile phones, laptop computers, and electric vehicles, the demand for small, lightweight, and relatively high-capacity rechargeable batteries is increasing rapidly. In particular, lithium-ion batteries are gaining attention as power sources for portable devices due to their lightweight nature and high energy density. Accordingly, research and development are being conducted to improve the capacity characteristics of lithium-ion batteries.

[0007] Recently, continuous attempts have been made to increase the capacity of lithium-ion batteries by increasing the nickel content among transition metals in lithium-nickel-based oxides or by operating the battery at high voltages to improve the energy density of the cathode active material. However, as the volume expands and contracts repeatedly during the cycle of lithium-ion batteries, the cathode degrades and cracks occur, leading to increased resistance and reduced lifespan characteristics. This problem can be exacerbated by increasing the nickel content among transition metals or operating the battery at high voltages.

[0008] To solve the above problems, a technology has been proposed to manufacture a cathode active material in the form of single particles rather than secondary particles by increasing the calcination temperature during the production of lithium nickel-based oxides. In the case of a cathode active material in the form of single particles, the contact area with the electrolyte is smaller compared to conventional cathode active materials in the form of secondary particles, so there are fewer side reactions with the electrolyte, and the particle strength is excellent, resulting in less particle breakage during electrode manufacturing. Therefore, when a cathode active material in the form of single particles is applied, there is an advantage of excellent gas generation and lifespan characteristics.

[0009] However, since the single-particle type cathode active material is manufactured by under-sintering at high temperatures, there are many defects within the crystal structure and high strain. When there are defects within the crystal structure and high strain, the movement of lithium ions is non-uniform, and localized insertion / extraction of lithium ions occurs, which accelerates the degradation of the crystal structure.

[0010]

[0011] The present invention aims to solve the above-mentioned problems and to provide a precursor for a positive electrode active material, a positive electrode active material, a positive electrode, a lithium secondary battery, and a method for manufacturing a precursor for a positive electrode active material that can solve defects and strain problems within the crystal structure.

[0012]

[0013] [1] The present invention provides a precursor for an anode active material comprising a nickel-based hydroxide containing 50 mol% or more of nickel among the total metals, a pore area ratio (PAR) of 5% to 10%, a span value defined by Formula 1 below of 0.58 or less, and a sphericity of 0.8 or more.

[0014] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0015] [2] The present invention, in [1] above, has an average particle size D of the precursor for the positive electrode active material. 50 The present invention provides a precursor for a positive electrode active material having a thickness of 2.0㎛ to 6.0㎛.

[0016] [3] The present invention provides a precursor for an anode active material, wherein, in [1] or [2], the nickel-based hydroxide comprises 50 mol% to 70 mol% of nickel in the total metal.

[0017] [4] The present invention provides a precursor for an anode active material, wherein, in at least one of [1] to [3], the nickel-based hydroxide is represented by the following chemical formula 1.

[0018] [Chemical Formula 1]

[0019] Ni x0 Co y0 M 1 z0 M 2 w0 (OH)2

[0020] In the above chemical formula 1,

[0021] 0.50≤x0<1.0, 0 <y0≤0.3, 0<z0≤0.4, 0≤w0≤0.1이고, M 1 is Mn, Al, or a combination thereof, and M 2It is one or more doping elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo.

[0022] [5] The present invention, in at least one of [1] to [4], wherein in Formula 1, 0.50≤x0≤0.7, 0 <y0≤0.15, 0<z0≤0.3, 0≤w0≤0.1이고, 1.5≤z0 / y0≤5.0인, 양극 활물질용 전구체를 제공한다.

[0023] [6] The present invention provides a positive electrode active material comprising a calcined mixture of a precursor for a positive electrode active material according to any one of [1] to [5] and a lithium raw material, and a lithium nickel-based oxide comprising 50 mol% or more of nickel among all metals excluding lithium, wherein the lithium nickel-based oxide is a single-particle type particle.

[0024] [7] The present invention provides a positive electrode active material, wherein, in [6] above, the lithium nickel-based oxide is represented by the following chemical formula 2.

[0025] [Chemical Formula 2]

[0026] Li 1+a1 [Ni x2 Co y2 M 3 z2 M 4 w2 ]O2

[0027] In the above chemical formula 2, 1.0≤1+a1≤1.5, 0.5≤x2<1, 0 <y2<0.3, 0<z2<0.4, 0≤w2≤0.1임. M 3 is Mn, Al, or a combination thereof, and M 4It is one or more doping elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo.

[0028] [8] The present invention, in [6] or [7], wherein in Formula 2, 0.5≤x2≤0.7, 0 <y2≤0.2, 0<z2≤0.3, 0≤w2≤0.1이고, 1.5≤z2 / y2≤5.0인, 양극 활물질을 제공한다.

[0029] [9] The present invention provides a positive electrode active material in which, in at least one of [6] to [8], the fine generation rate of the positive electrode active material is 3.0 volume% or less.

[0030]

[0010] The present invention, in at least one of [6] to [9], wherein the positive active material has an average particle size D 50 This provides a positive electrode active material having a diameter of 2 to 6 μm.

[0031]

[0011] The present invention provides a positive active material, wherein in at least one of [6] to

[0010] , the positive active material has a SPAN value of 0.5 to 2.5 as defined by Formula 1 below.

[0032] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0033]

[0012] The present invention provides a positive electrode active material in which, in at least one of [6] to

[0011] , the degree of single particle size of the positive electrode active material is 2.8 or higher.

[0034]

[0013] The present invention provides a positive electrode active material in which, in at least one of [6] to

[0012] , the positive electrode active material has a nickel disorder (Ni-disorder) greater than 0% and less than 5%.

[0035]

[0014] The present invention provides a positive electrode comprising a positive electrode active material according to any one of [6] to

[0013] .

[0036]

[0015] The present invention provides a lithium secondary battery comprising: a positive electrode according to

[0014] ; a negative electrode disposed opposite to the positive electrode; and an electrolyte.

[0037]

[0016] The present invention provides a method for manufacturing a precursor for an anode active material, comprising: a nucleation step of preparing a reaction solution containing a precursor nucleus for an anode active material formed by supplying and reacting a metal solution containing 50 mol% or more of nickel among the total metals, an ammonium cation complex forming agent, and a basic solution in a first reactor, and moving the reaction solution from the first reactor to a second reactor; and a particle growth step of growing precursor particles for an anode active material by co-precipitating the reaction solution in which the precursor nucleus for an anode active material is formed in the second reactor while supplying the metal solution, the ammonium cation complex forming agent, and a basic compound to the reaction solution, wherein the particle growth step is performed in an oxidizing atmosphere, and the oxidizing atmosphere is formed by introducing an oxygen-containing gas in an amount such that the amount of oxygen per 1 kg of transition metal in the metal solution is 30 L to 50 L.

[0038]

[0017] The present invention provides a method for manufacturing a precursor for an anode active material, wherein, in the particle forming step

[0016] , the metal solution is supplied at a first flow rate and then supplied at a second flow rate that is 1.5 to 2.5 times the first flow rate.

[0039]

[0018] The present invention provides a method for manufacturing a precursor for an anode active material, wherein in the particle formation step of

[0016] or

[0017] , the pH of the reaction solution is 10.5 to 12.5.

[0040]

[0041] The precursor for a positive electrode active material according to the present invention comprises a nickel-based hydroxide containing 50 mol% or more of nickel among the total metals, has a pore area ratio (PAR) of 5 to 10%, a span value defined by a specific formula of 0.58 or less, and a sphericity of 0.8 or more. By including nickel in a certain mol% or more, the precursor for a positive electrode active material according to the present invention may have excellent capacity characteristics. However, when the precursor for a positive electrode active material is calcined at a high temperature, defects and / or strain may occur in the crystal structure of the manufactured positive electrode active material, or the reaction with the lithium raw material may occur unevenly. Therefore, by ensuring that the pore area ratio, span value, and sphericity simultaneously satisfy specific ranges as described above, the particle uniformity of the precursor for a positive electrode active material can be controlled, thereby improving reactivity with the lithium raw material during calcination of the precursor for a positive electrode active material and improving defects and / or strain within the crystal structure.

[0042] Accordingly, the positive electrode active material manufactured using the precursor for the positive electrode active material according to the present invention has reduced particle breakage even after rolling, and the degradation of the crystal structure due to repeated charging and discharging can be suppressed.

[0043] The positive electrode to which the positive electrode active material according to the present invention is applied can suppress the increase in resistance during charging and discharging, and consequently, the lifespan characteristics of a lithium secondary battery including the positive electrode according to the present invention can be improved.

[0044]

[0045] The present invention will be described in more detail below.

[0046] Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0047] The terms used in this specification are used merely to describe exemplary embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

[0048] In this specification, terms such as “comprising,” “having,” or “having” are intended to specify the existence of the implemented features, numbers, steps, components, or combinations thereof, and should be understood as not excluding in advance the existence or addition of one or more other features, numbers, steps, components, or combinations thereof.

[0049] In the present invention, "single-particle type particle" refers to a particle formed by the aggregation of 30 or fewer sub-particles. The sub-particle unit constituting the single-particle type particle is referred to as a nodule. Single-particle type particles include a single particle consisting of one nodule and a pseudo-single particle which is a composite of 2 to 30 nodules.

[0050] The above “nodule” is a sub-grain unit constituting a single particle and a pseudo-single particle, and may be a single crystal that does not have crystalline grain boundaries, or a polycrystalline one in which no grain boundaries appear to exist when observed at a field of view of 5,000 to 20,000 times using a scanning electron microscope.

[0051] In the present invention, "secondary particle" refers to a particle formed by the aggregation of more than 30 sub-particles. To distinguish it from the sub-particles constituting a single-particle type particle, the sub-particles constituting the secondary particle are called "primary particles."

[0052] In the present invention, the term “particle” is a concept that includes any one or all of a single particle, a pseudo-single particle, a primary particle, a nodule, and a secondary particle.

[0053] In the present invention, "Pore Area Ratio (PAR)" refers to the ratio of the pore area to the internal area of ​​a particle. Specifically, the Pore Area Ratio (PAR) can be measured by 2Dizing the particles using an image obtained through scanning electron microscope (SEM) imaging of the positive electrode active material or positive electrode active material precursor particles, and then performing pore distribution analysis on the 2Dized image using an image analysis program. For example, a positive electrode slurry is prepared by mixing the positive electrode active material or positive electrode active material precursor with carbon black and a PVDF binder in N-methylpyrrolidone at a weight ratio of 95:2:3, and the positive electrode slurry is applied to one surface of an aluminum current collector with a thickness of 20 μm. The coated anode composite layer is dried at 130°C to produce an electrode, and the electrode is used with image analysis software WinRoof 6.1.1 to display the void portions within the anode active material precursor or anode active material particles as shading and the dense portions within the anode active material precursor or anode active material particles as white. For any 20 or more anode active material precursors or anode active material particles among the measured anode active material precursors or anode active materials, the ratio (%) can be calculated as [shaded portion / (shaded portion + white portion) × 100] for each, thereby obtaining the pore area ratio (PAR).

[0054] In the present invention, "sphericity" refers to a value derived from the minimum particle diameter (Dmin, short diameter), maximum particle diameter (Dmax, long diameter), and area of ​​particles obtained by two-dimensionalizing particles using an image obtained through scanning electron microscope (SEM) imaging of a positive electrode active material or a precursor particle for a positive electrode active material, and using an image analysis program on the two-dimensionalized image. It represents the average value of tens to hundreds, preferably 300 particles in the present invention, and is specifically calculated using the following Equation A.

[0055] [Equation A] Roundness = (4 × Area) / (π × (D max ) 2 )

[0056] In addition, in this specification, the sphericity is a value derived from a scanning electron microscope image, so it is substantially no different from the meaning of 'circularity'; however, the value analyzed as circularity in image interpretation is expressed as sphericity considering that the positive active material or the precursor particle for the positive active material is a three-dimensional particle.

[0057] In the present invention, "average particle size D 50 "This refers to the particle size corresponding to 50% of the volume cumulative amount of the volume cumulative particle size distribution of the powder to be measured, and can be measured using the laser diffraction method. For example, the powder to be measured can be measured by dispersing it in a dispersion medium, introducing it into a commercially available laser diffraction particle size measuring device (e.g., Microtrac MT 3000), irradiating it with ultrasound of about 28 kHz at an output of 60 W, obtaining a volume cumulative particle size distribution graph, and then determining the particle size corresponding to 50% of the volume cumulative amount.

[0058] In the present invention, “D 90"This refers to the particle size corresponding to 90% of the volume cumulative amount of the volume cumulative particle size distribution of the powder to be measured, and can be measured using the laser diffraction method. For example, the powder to be measured can be measured by dispersing it in a dispersion medium, introducing it into a commercially available laser diffraction particle size measuring device (e.g., Microtrac MT 3000), irradiating it with ultrasound of about 28 kHz at an output of 60 W, obtaining a volume cumulative particle size distribution graph, and then determining the particle size corresponding to 90% of the volume cumulative amount.

[0059] In the present invention, “D 10 "This refers to the particle size corresponding to 10% of the volume cumulative amount of the volume cumulative particle size distribution of the powder to be measured, and can be measured using the laser diffraction method. For example, the powder to be measured can be measured by dispersing it in a dispersion medium, introducing it into a commercially available laser diffraction particle size measuring device (e.g., Microtrac MT 3000), irradiating it with ultrasound of about 28 kHz at an output of 60 W, obtaining a volume cumulative particle size distribution graph, and then determining the particle size corresponding to 10% of the volume cumulative amount.

[0060] In the present invention, "strain" refers to the distortion of the lattice caused by a defect, i.e., micro-deformation. The strain was measured by analyzing XRD data obtained by X-ray diffraction analysis of the cathode active material powder using the Rietveld refinement method. At this time, the X-ray diffraction analysis can be performed using a Bruker D8 Endeavor equipped with a LynxEye XE-T-position sensitive detector (light source: Cu-Kα, λ=1.54Å). The sample is placed in the groove of a general powder holder, the sample surface is smoothed using a slide glass, and the sample is filled so that its height aligns with the edge of the holder. Measurements can then be taken under conditions of FDS 0.5°, 2θ = 15° to 90°, a step size of 0.02°, and a total scan time of approximately 20 minutes. Rietveld refinement can be performed on the measured data by considering the charge at each site (metals at transition metal sites are +3, and Ni at Li sites is +2) and cation mixing. Specifically, during strain analysis, instrumental broadening can utilize the Fundamental Parameter Approach (FPA) implemented in the Bruker TOPAS program, and during fitting, all peaks of the measurement range It can be used. The peak shape can be fitted using only the Lorenzian contribution as the FP (First Principle) among the peak types available in TOPAS.

[0061] In the present invention, “fine particle generation rate” refers to the volume percentage of fine particles with a particle size of 1 μm or less based on the total weight of the positive active material powder when the positive active material is pressed with a force of 12 tons. For example, the fine particle generation rate can be obtained by placing the positive active material in powder form into a cylindrical metal mold with a diameter of 13 mm, pressing it with a force of 12 tons, then dispersing it again in a dispersion medium, obtaining a Particle Size Distribution (PSD) using a laser diffraction particle size measuring device (Malvern, Mastersizer 3000), and then calculating the volume ratio of fine particles with a particle size of 1 μm or less in the total positive active material powder.

[0062] In the present invention, the “single particle size” can be obtained according to the following formula B.

[0063] [Equation B]

[0064]

[0065] In the above equation B, R i is the unitless number of the half-diameter (unit: μm) of the i-th grain measured when the electrode cross-section is analyzed by Electron Backscatter Diffraction (EBSD) after ion milling the electrode manufactured using the target positive active material precursor or positive active material powder, and n is the unitless number of the total number of grains measured through the EBSD analysis. n is 200 to 500.

[0066] In the present invention, the “nickel disorder” is determined by obtaining XRD data using an X-ray diffraction analyzer (Bruker, D8 Endeavor) and then performing atomic structure analysis using the Rietveld method, wherein the Ni occupying the lithium sites 2+After analyzing the relative amount of ions and the relative occupancy by oxygen at oxygen sites, respectively, the irregular Ni at lithium sites obtained therefrom 2+ It can mean the ion amount (%).

[0067]

[0068] The present invention will be described in detail below.

[0069] A precursor for a positive electrode active material according to the present invention, a method for manufacturing the same, a positive electrode active material, a positive electrode, a lithium secondary battery, and a method for manufacturing a precursor for a positive electrode active material comprise at least one of the configurations disclosed below, and may comprise any combination of technically feasible configurations among the configurations below.

[0070]

[0071] Precursor for positive electrode active material

[0072] The precursor for a positive electrode active material according to the present invention comprises a nickel-based hydroxide containing 50 mol% or more of nickel among the total metals. Specifically, the precursor for a positive electrode active material may comprise a nickel-based hydroxide containing 50 mol% or more, 52 mol% or more, 54 mol% or more, 55 mol% or more, 56 mol% or more, 58 mol% or more, 60 mol% or more, 80 mol% or less, 75 mol% or less, 70 mol% or less, 65 mol% or less, or 60 mol% or less of nickel among the total metals. For example, the precursor for a positive electrode active material may comprise a nickel-based hydroxide containing 50 mol% or more, 50 mol% to 80 mol%, 50 mol% to 70 mol%, or 55 mol% to 65 mol% of nickel among the total metals. If the above range is satisfied, a positive electrode active material with high energy density can be manufactured, which can result in excellent battery capacity characteristics and reduce electrolyte side reactions and gas generation.

[0073]

[0074] The above nickel-based hydroxide can be represented by the following chemical formula 1.

[0075] [Chemical Formula 1]

[0076] Ni x0 Co y0 M 1 z0 M 2 w0 (OH)2

[0077] In the above chemical formula 1, M 1 can be Mn, Al, or a combination thereof. The above M 1 If included, the structural stability of nickel-based hydroxides can be improved.

[0078] In the above chemical formula 1, M 2 ... may be one or more doping elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, or may be one or more doping elements selected from the group consisting of W, Y, Ba, Ca, Ti, Mg, Ta, and Nb. 2 It may be optionally included in or not included in the nickel-based hydroxide represented by the above chemical formula 1, and if included, it may play a role in facilitating calcination or improving structural stability.

[0079] In the above chemical formula 1, x0 represents the molar ratio of nickel to the total metal in the nickel-based hydroxide particles, and may be 0.50≤x0<1.0, 0.50≤x0≤0.80, 0.50≤x0≤0.70, or 0.55≤x0≤0.65. When the above range is satisfied, the capacity characteristics and structural stability of the manufactured cathode active material may be excellent.

[0080] In the above Chemical Formula 1, y0 represents the molar ratio of cobalt among the total metals in the nickel-based hydroxide particles, where 0 <y0≤0.3, 0<y0≤0.2, 0<y0≤0.15, 또는 0.05≤y0≤0.12일 수 있다. 상기 범위를 만족하는 경우, 비용적인 이점을 가지면서, 출력 특성이 개선될 수 있다.

[0081] In the above Chemical Formula 1, z0 is M of the total metal in the nickel-based hydroxide particles. 1 It refers to the molar ratio of, 0 <z0≤0.4, 0<z0≤0.37, 0.1≤z0≤0.35, 0.2≤z0≤0.33 또는 0.25≤z0≤0.32일 수 있다. 상기 범위를 만족하는 경우, 상기 화학식 1로 표시되는 양극 활물질용 전구체를 이용하여 제조된 양극 활물질의 구조적 안정성이 개선될 수 있다.

[0082] In the above Chemical Formula 1, w0 is M of the total metal in the nickel-based hydroxide particles 2 It refers to the molar ratio, which may be 0≤w0≤0.1, 0≤w0≤0.08, 0≤w0≤0.05, or 0≤w0≤0.01. When the above range is satisfied, it can play a role in promoting particle growth during calcination of the positive active material prepared using the precursor for the positive active material represented by Chemical Formula 1, or improving crystal structure stability.

[0083]

[0084] The above precursor for the positive electrode active material may include a nickel-based hydroxide comprising nickel, cobalt, and manganese. For example, the above precursor for the positive electrode active material may include a nickel-based hydroxide represented by the following chemical formula 1-1. When the nickel-based hydroxide includes manganese, structural stability may be improved as the manganese contributes to maintaining the layered structure of the nickel-based hydroxide.

[0085] [Chemical Formula 1-1]

[0086] Ni x1 Coy1 Mn z1 M 2 w1 (OH)2

[0087] In the above chemical formula 1-1, M 2 ... may be one or more doping elements selected from the group consisting of Al, W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, or may be one or more doping elements selected from the group consisting of Al, W, Y, Ba, Ca, Ti, Mg, Ta, and Nb. 2 It may be optionally included in or not included in the nickel-based hydroxide represented by the above chemical formula 1-1, and if included, it may play a role in facilitating calcination or improving structural stability.

[0088] In the above chemical formula 1-1, x1 represents the molar ratio of nickel to the total metal in the nickel-based hydroxide particles, and may be 0.50≤x1<1.0, 0.50≤x1≤0.80, 0.50≤x1≤0.70, or 0.55≤x1≤0.65. When the above range is satisfied, the capacity characteristics of the cathode active material prepared using the nickel-based hydroxide represented by the above chemical formula 1-1 may be excellent.

[0089] In the above chemical formula 1-1, y1 represents the molar ratio of cobalt among the total metals in the nickel-based hydroxide particles, where 0 <y1≤0.3, 0<y1≤0.2, 0<y1≤0.15, 또는 0.05≤y1≤0.12일 수 있다. 상기 범위를 만족하는 경우, 비용적인 이점을 가지면서, 출력 특성이 개선될 수 있다.

[0090] In the above Chemical Formula 1-1, z1 represents the molar ratio of manganese among the total metals in the nickel-based hydroxide particles, where 0 <z1≤0.4, 0<z1≤0.37, 0.1≤z1≤0.35, 0.2≤z1≤0.33 또는 0.25≤z1≤0.32일 수 있다. 상기 범위를 만족하는 경우, 상기 화학식 1-1으로 표시되는 니켈계 수산화물을 이용하여 제조된 양극 활물질의 구조적 안정성이 개선될 수 있다.

[0091] In the above chemical formula 1-1, w1 is M of the total metal in the nickel-based hydroxide particle. 2 It refers to the molar ratio of 0≤w1≤0.1, 0≤w1≤0.08, 0≤w1≤0.05, or 0≤w1≤0.01. When the above range is satisfied, the structural stability of the cathode active material prepared using the nickel-based hydroxide represented by Chemical Formula 1-1 can be improved.

[0092]

[0093] In the above formula 1 or formula 1-1, the x0 / y0 or x1 / y1 may be 3.2 or more, 3.4 or more, 3.5 or more, 3.6 or more, 3.8 or more, 4.0 or more, 4.2 or more, 4.4 or more, 4.6 or more, 4.8 or more, 5.0 or more, 5.2 or more, 5.4 or more, 5.6 or more, 5.8 or more, 6.0 or more, 9.0 or less, 8.8 or less, 8.6 or less, 8.5 or less, 8.4 or less, 8.2 or less, 8.0 or less, 7.8 or less, 7.6 or less, 7.5 or less, 7.4 or less, 7.2 or less, 7.0 or less, 6.8 or less, 6.6 or less, 6.4 or less, 6.2 or less, or 6.0 or less. For example, the above x0 / y0 or x1 / y1 may be 3.2 to 9.0, 3.5 to 8.5, 4.0 to 8.0, 4.5 to 7.5, 5.0 to 7.0, or 5.5 to 6.5. When the above range is satisfied, the manufactured cathode active material can achieve high capacity by containing a high amount of nickel (Ni), and the crystal structure of the cathode may not collapse after the high capacity is achieved, so the lifespan characteristics are excellent.

[0094] In the above formula 1 or formula 1-1, the x0 / z0 or x1 / z1 may be 1.0 or more, 1.1 or more, 1.2 or more, 1.3 or more, 1.4 or more, 1.5 or more, 1.6 or more, 1.7 or more, 1.8 or more, 1.9 or more, 2.0 or more, 2.8 or less, 2.7 or less, 2.6 or less, 2.5 or less, 2.4 or less, 2.3 or less, 2.2 or less, 2.1 or less, or 2.0 or less. For example, the x0 / z0 or x1 / z1 may be 1.0 to 2.8, 1.2 to 2.6, 1.4 to 2.5, 1.6 to 2.4, 1.8 to 2.2, or 1.9 to 2.1. When the above range is satisfied, variability in the c-axis direction within the layered structure during charging and discharging is suppressed by manganese (Mn), and at the same time, stable capacity development by nickel (Ni) is possible, so the electrochemical characteristics of the battery can be excellent.

[0095] In the above Chemical Formula 1 or above Chemical Formula 1-1, the z0 / y0 or z1 / y1 is 1.5 or more, 1.6 or more, 1.7 or more, 1.8 or more, 1.9 or more, 2.0 or more, 2.1 or more, 2.2 or more, 2.3 or more, 2.4 or more, 2.5 or more, 2.6 or more, 2.7 or more, 2.8 or more, 2.9 or more, 3.0 or more, 5.0 or less, 4.9 or less, 4.8 or less, 4.7 or less, 4.6 or less, 4.5 or less, 4.4 or less, 4.3 or less, 4.2 or less, 4.1 or less, 4.0 or less, 3.9 or less, 3.8 or less, 3.7 or less, 3.6 or less, 3.5 or less, 3.4 or less, 3.3 or less, 3.2 or less, 3.1 or less, or It may be 3.0 or less. For example, the above z0 / y0 or z1 / y1 may be 1.5 to 5.0, 1.7 to 4.5, 2.0 to 4.0, 2.2 to 3.8, 2.5 to 3.5, 2.7 to 3.3, or 2.9 to 3.1. When the above range is satisfied, the manganese content can be increased relatively compared to cobalt, so the structural stability of the cathode active material prepared by calcining the cathode active material is excellent, so it can have excellent stability at high temperature and high voltage, and can have cost advantages.

[0096]

[0097] The above precursor for the positive electrode active material has a pore area ratio (PAR) of 5 to 20%. Specifically, the above precursor for the positive electrode active material may have a pore area ratio of 5% or more, 6% or more, 7% or more, 7.5% or more, 10% or less, 9% or less, 8.5% or less, 8% or less, or 7.6% or less. For example, the above precursor for the positive electrode active material may have a pore area ratio of 5% to 10%, 6% to 9%, 6.5% to 8.5%, or 7% to 9%. If the above pore area ratio is too low, there is a lack of pores, so the reaction with lithium does not occur easily, resulting in inferior particle size. If the above pore area ratio is too high, the particle size increases too much, hindering the movement of lithium ions during charging and discharging, which increases the resistance growth rate and may result in inferior lifespan characteristics. Therefore, if the above range is satisfied, internal pores can aid in crystal growth during high-temperature calcination, thereby controlling particle uniformity and improving reactivity with lithium raw materials during high-temperature calcination, which allows for the formation of a stable crystal structure and suppressing defects and strain within the crystal structure. Consequently, the resistance characteristics and lifespan characteristics of a cathode and battery using the manufactured cathode active material can be improved. The above pore area ratio can be controlled by controlling the amount of oxygen input, the flow rate of the metal solution, the pH of the reaction solution, the reaction time, etc., during the particle formation stage of the method for manufacturing a precursor for a cathode active material.

[0098] The precursor for the positive electrode active material has a SPAN value defined by Formula 1 below of 0.58 or less. Specifically, the precursor for the positive electrode active material may have a SPAN value defined by Formula 1 below of 0.58 or less, 0.56 or less, 0.54 or less, 0.52 or less, 0.5 or less, 0.48 or less, 0.1 or more, 0.15 or more, 0.2 or more, 0.25 or more, 0.3 or more, 0.35 or more, 0.4 or more, 0.45 or more, or 0.48 or more. For example, the precursor for the positive electrode active material may have a SPAN value defined by Formula 1 below of 0.58 or less, 0.1 to 0.58, 0.2 to 0.56, 0.3 to 0.54, 0.4 to 0.52, or 0.45 to 0.5. When the span value of the precursor for the positive electrode active material satisfies the above range, uniform calcination with lithium is possible due to the uniform particle size distribution of the precursor, and as a result, the effect of reducing defects and strain within the structure of the positive electrode active material occurs.

[0099] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0100] The above span value can be controlled by controlling the amount of oxygen input, the flow rate of the metal solution, the pH of the reaction solution, the reaction time, etc., during the particle formation step in the method for manufacturing a precursor for a positive electrode active material.

[0101]

[0102] Average particle size D of the precursor for the positive electrode active material of the present invention 50 The range may be 2.0㎛ to 6.0㎛, 2.5㎛ to 5.5㎛, 3㎛ to 5㎛, or 3.2㎛ to 4㎛. When the above range is satisfied, the lithium ion diffusion path is short, the contact area with the electrolyte is increased, and particle cracking during charging and discharging can be suppressed, so that the capacity, output, and lifespan characteristics may be excellent.

[0103] D of the precursor for the positive electrode active material of the present invention90 The range may be 2㎛ to 7㎛, 2.5㎛ to 6.5㎛, or 3.5㎛ to 5.5㎛. If the above range is satisfied, the span value may satisfy the desired range.

[0104] D of the precursor for the positive electrode active material of the present invention 10 The range may be 0.5㎛ to 5㎛, 1㎛ to 4㎛, or 1.5㎛ to 3.5㎛. If the above range is satisfied, the span value may satisfy the desired range.

[0105]

[0106] The precursor for the positive electrode active material has a sphericity of 0.8 or higher. Specifically, the precursor for the positive electrode active material may have a sphericity of 0.8 or higher, 0.81 or higher, 0.82 or higher, 0.83 or higher, 0.84 or higher, 0.85 or higher, 0.86 or higher, 0.87 or higher, 0.88 or higher, 0.89 or higher, 0.9 or higher, 0.91 or higher, 0.92 or higher, 0.93 or higher, 0.94 or higher, 0.95 or higher, less than 1, 0.99 or lower, 0.98 or lower, 0.97 or lower, or 0.95 or lower. For example, the precursor for the positive electrode active material may have a sphericity of 0.8 or higher, 0.81 or higher, 0.82 or higher, 0.83 to 0.99, or 0.83 to 0.98. When the above range is satisfied, heat can be transferred uniformly when the precursor for the positive electrode active material is calcined at high temperature, and stress is evenly distributed throughout the particles, allowing for control of particle uniformity during high-temperature calcination, thereby enabling stable crystal growth and reducing the occurrence of defects or strain. The degree of sphericity can be controlled by controlling the amount of oxygen input, the flow rate of the metal solution, the pH of the reaction solution, the reaction time, etc., during the particle formation stage of the method for manufacturing the precursor for the positive electrode active material.

[0107]

[0108] Method for manufacturing a precursor for a positive electrode active material

[0109] A method for manufacturing a precursor for a positive electrode active material according to the present invention comprises: (1) a nucleation step of supplying and reacting a metal solution containing 50 mol% or more of nickel among the total metals, an ammonium cation complex forming agent, and a basic solution in a first reactor to form a reaction solution containing a nucleus for a positive electrode active material, and moving the reaction solution from the first reactor to a second reactor; and (2) a particle growth step of growing a precursor particle for a positive electrode active material by co-precipitating the reaction solution in which the nucleus for a positive electrode active material has been formed in the second reactor while supplying the metal solution, the ammonium cation complex forming agent, and a basic compound.

[0110] The particle growth step described above is performed in an oxidizing atmosphere, and the oxidizing atmosphere can be formed by introducing an oxygen-containing gas in an amount such that the oxygen content per 1 kg of transition metal in the transition metal aqueous solution is 20 L to 60 L, 30 L to 50 L, 32 L / kg to 48 L / kg, or 35 L / kg to 45 L / kg. When the above ranges are satisfied, crystal growth can occur more densely and slowly, allowing control so that the grown precursor for the positive electrode active material has a uniform shape and sufficient pores are formed. Accordingly, a precursor for the positive electrode active material can be formed that satisfies the desired ranges for SPAN value, sphericity, and pore area ratio.

[0111] The above oxygen-containing gas may be a gas with an oxygen content of 21% or more, such as the atmosphere, for example, or a gas with an oxygen content of 25% or more.

[0112] According to the above method for manufacturing a precursor for a positive active material, the aforementioned precursor particles for a positive active material can be manufactured. Specifically, the precursor particles for a positive active material manufactured according to the above method for manufacturing a precursor for a positive active material contain a nickel-based hydroxide containing 50 mol% or more of nickel among the total metals, have a pore area ratio (PAR) of 5% to 10%, a span value defined by Formula 1 below of 0.58 or less, and a degree of sphericity of 0.8 or more.

[0113] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0114]

[0115] Hereinafter, each step of the method for manufacturing a precursor for a positive electrode active material according to the present invention will be described in detail.

[0116]

[0117] (1) Nucleation stage

[0118] First, a metal solution containing 50 mol% or more of nickel among the total metals, an ammonium cation complex forming agent, and a basic solution are supplied to a first reactor and reacted to form a reaction solution containing a precursor nucleus for a positive electrode active material.

[0119] It is preferable that the first reactor above be a batch reactor. This is because it is difficult to control the particle size of the precursor particles when manufacturing the precursor using a Continuous Stirred-Tank Reactor (CSTR).

[0120] The first reactor may include a reaction mother liquor. Specifically, before supplying the reaction raw materials, such as a metal solution, an ammonium cation complex forming agent, and a basic compound, the ammonium cation complex forming agent, the basic compound, and water may be first introduced into the first reactor to form a reaction mother liquor.

[0121] The ammonium cation complex forming agent may be at least one selected from the group consisting of NH4OH, (NH4)2SO4, NH4NO3, NH4Cl, CH3COONH4, and NH4CO3, and may be introduced into a reactor in the form of a solution in which the compound is dissolved in a solvent. At this time, the solvent may be water, or a mixture of water and an organic solvent (specifically, alcohol, etc.) that is uniformly miscible with water.

[0122] The above basic compound may be at least one selected from the group consisting of NaOH, KOH, and Ca(OH)2, and may be introduced into the reactor in the form of a solution in which the compound is dissolved in a solvent. In this case, water or a mixture of water and an organic solvent that is uniformly miscible with water (specifically, alcohol, etc.) may be used as the solvent.

[0123] The above reaction mother liquor can be formed such that its pH is 11.0 to 13.0, 11.2 to 12.8, 11.5 to 12.5, or 11.7 to 12.1. When the pH of the reaction mother liquor satisfies the above range, nucleation can be carried out smoothly.

[0124] After forming a reaction mother liquor by introducing an ammonium cation complex forming agent, a basic compound, and water into a first reactor, oxygen in the reaction mother liquor can be removed by purging with nitrogen gas.

[0125]

[0126] Next, a metal solution, an ammonium cation complex forming agent, and a basic solution are supplied to a first reactor and reacted to form a reaction solution containing a precursor nucleus for the positive electrode active material.

[0127] When a metal solution, an ammonium cation complex forming agent, and a basic compound are supplied to a first reactor containing a reaction mother liquor and stirred, a co-precipitation reaction proceeds, generating precursor nuclei in the form of primary particles, and as the nuclei in the form of primary particles aggregate, seed nuclei in the form of secondary particles are formed.

[0128] In the above nucleation step, the metal solution may be supplied at a flow rate of 0.1 L / h to 1 L / h, 0.2 L / h to 0.8 L / h, or 0.3 L / h to 0.6 L / h. The above flow rate may be the average flow rate value during the nucleation reaction. If the above range is satisfied, nuclei having an appropriate density gradient can be formed.

[0129] In the above nucleation step, the ammonium cation complex forming agent may be supplied at a flow rate of 0.1 L / h or less, 0.01 L / h to 0.08 L / h, or 0.01 L / h to 0.06 L / h. When the above range is satisfied, nuclei are formed smoothly, the growth rate of the nuclei can be maintained, and the degree of sphericity can be improved.

[0130] In the above nucleation step, the basic compound may be supplied at a flow rate of 0.1 L / h to 2 L / h, 0.2 L / h to 1.5 L / h, or 0.5 L / h to 1.0 L / h. If the above ranges are satisfied, the pH of the reaction solution can be maintained within an appropriate range.

[0131] The above metal solution contains nickel (Ni) in an amount of 50 mol% or more, 50 mol% to 80 mol%, 50 mol% to 70 mol%, or 55 mol% to 65 mol% of the total metal. When the above range is satisfied, structural stability can be improved while further improving capacity characteristics.

[0132]

[0133] The above metal solution is optionally cobalt, M 1 Element (M above) 1 (Silver, manganese, aluminum, or a combination thereof) and / or M2 Element (M 2 It may include one or more selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo.

[0134] The above metal solution comprises a nickel-containing raw material, optionally a cobalt-containing raw material, M 1 Containing raw materials and / or M 2 It is prepared by adding a containing raw material to a solvent, specifically water, or a mixed solvent of an organic solvent that can be uniformly mixed with water (e.g., alcohol, etc.), or an aqueous solution of a nickel-containing raw material, an aqueous solution of a cobalt-containing raw material, M 1 Aqueous solution of the contained raw material, M 2 It may be manufactured by mixing an aqueous solution of the contained raw material.

[0135] The above nickel-containing raw material may be nickel-containing acetate, nitrate, sulfate, halide, sulfide, hydroxide, oxide, or oxyhydroxide, and specifically, may be Ni(OH)2, NiO, NiOOH, NiCO3·2Ni(OH)2·4H2O, NiC2O2·2H2O, Ni(NO3)2·6H2O, NiSO4, NiSO4·6H2O, nickel salts of fatty acids, or nickel halides, and any one or more of these may be used.

[0136] The above cobalt-containing raw material may be a cobalt-containing acetate, nitrate, sulfate, halide, sulfide, hydroxide, oxide, or oxyhydroxide, etc., and may be Co(OH)2, CoOOH, Co(OCOCH3)2ㆍ4H2O, Co(NO3)2ㆍ6H2O or Co(SO4)2ㆍ7H2O, etc., and any one or more of these may be used.

[0137] The above M 1In the contained raw material, M 1 It may be one or more of aluminum and manganese, and the above M 1 The contained raw material is M 1 It may be an acetate, nitrate, sulfate, halide, sulfide, hydroxide, oxide, or oxyhydroxide containing an element, etc. Specifically, the above M 1 The contained raw materials may be manganese oxides such as Mn2O3, MnO2, Mn3O4, etc.; manganese salts such as MnCO3, Mn(NO3)2, MnSO4, manganese acetate, manganese dicarboxylate, manganese citrate, manganese fatty acid, manganese oxyhydroxide, manganese chloride; Al2O3, AlSO4, AlCl3, Al-isopropoxide, AlNO3, or combinations thereof, but are not limited thereto.

[0138] The above M 2 In the contained raw material, M 2 The element may include one or more selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and M 2 The contained raw material is the above M 2 It may be an acetate, nitrate, sulfate, halide, sulfide, hydroxide, oxide, or oxyhydroxide containing the element.

[0139]

[0140] The above metal solution may contain cobalt in an amount of 30 mol% or less, 20 mol% or less, 1 mol% to 15 mol%, or 5 mol% to 12 mol% of the total metal. When the above range is satisfied, the structural stability is relatively improved, and cost advantages may be obtained.

[0141] The above metal solution is M among the total metals 1It may contain 40 mol% or less, 37 mol% or less, 10 mol% to 35 mol%, 20 mol% to 33 mol%, or 25 mol% to 32 mol%. If the above range is satisfied, structural stability may be improved.

[0142] In the above metal solution, the ratio of the molar ratio of nickel to the molar ratio of cobalt may be 3.2 to 9.0, 3.5 to 8.5, 4.0 to 8.0, 4.5 to 7.5, 5.0 to 7.0, or 5.5 to 6.5. When the above range is satisfied, the finally manufactured cathode active material can achieve high capacity by containing a high content of nickel (Ni), and the crystal structure of the cathode may not collapse after the high capacity is achieved, so the lifespan characteristics are excellent.

[0143] In the above metal solution, M 1 The ratio of the molar ratio of nickel to the molar ratio of may be 1.0 to 2.8, 1.2 to 2.6, 1.4 to 2.5, 1.6 to 2.4, 1.8 to 2.2, or 1.9 to 2.1. When the above range is satisfied, the variability in the c-axis direction within the layered structure of the finally manufactured positive electrode active material during charging and discharging is suppressed by manganese (Mn), and at the same time, the capacity development by nickel (Ni) can be stably achieved, so the electrochemical characteristics of the battery may be excellent.

[0144] In the above metal solution, M for the molar ratio of cobalt 1 The molar ratio of may be 1.5 to 5.0, 1.7 to 4.5, 2.0 to 4.0, 2.2 to 3.8, 2.5 to 3.5, 2.7 to 3.3, or 2.9 to 3.1. When the above range is satisfied, the structural stability of the finally manufactured cathode active material is excellent, so it can have excellent stability at high temperature and high voltage, and can have cost advantages.

[0145] The content of the transition metal included in the metal solution supplied in the above nucleation step may be 1.5 mol / L to 2.5 mol / L, or 1.8 mol / L to 2.3 mol / L.

[0146]

[0147] In the nucleation step, the pH of the reaction solution may be 11.0 to 13.0, 11.2 to 12.8, 11.5 to 12.5, or 11.7 to 12.1. Nuclei of the cathode active material precursors are formed within the reaction solution, and the process of nucleation by aggregating the nuclei can proceed smoothly. The pH of the reaction solution can be controlled by adjusting the amount of basic compound added using a pH sensor or the like.

[0148] The nucleation step can be performed at a temperature of 40°C to 80°C, 45°C to 70°C, or 45°C to 60°C. If the above temperature range is satisfied, precursor nuclei for the positive electrode active material can be smoothly generated.

[0149] The reaction of the nucleation step described above can be carried out for 2 to 20 hours, or 4 to 15 hours. If the above range is satisfied, the particle size distribution of the precursor particles can be uniform, and productivity can be excellent.

[0150] The reaction of the nucleation step described above can be carried out while stirring the reaction solution, wherein the stirring speed may be 50 rpm to 1000 rpm, 100 rpm to 600 rpm, 200 rpm to 400 rpm, or 250 rpm to 350 rpm. When the stirring speed satisfies the above range, a precursor with a high degree of sphericity can be formed.

[0151]

[0152] When the reaction is completed after sufficient nuclei of the precursor for the positive electrode active material are formed in the above nucleation step, the reaction solution can be transferred from the first reactor to the second reactor. By transferring the reaction solution from the first reactor to the second reactor to perform the particle growth step described later, the flow rate of the metal solution can be easily controlled, thereby lowering the particle growth rate of the precursor. Consequently, a precursor for the positive electrode active material can be manufactured with span values ​​and sphericity adjusted to the desired range.

[0153]

[0154] The above nucleation step involves the average particle size D of the precursor nucleus for the positive electrode active material. 50 This can be performed to be 1㎛ to 5㎛, 1.2㎛ to 4㎛, 1.5㎛ to 3㎛, or 1.8㎛ to 2.2㎛.

[0155]

[0156] (2) Particle growth stage

[0157] Through the above process, nuclei are sufficiently formed, and after transferring the reaction solution from the first reactor to the second reactor, precursor particles for the positive active material are grown by co-precipitating them in the second reactor while supplying a metal solution, an ammonium cation complex forming agent, and a basic compound to the reaction solution in which the precursor nuclei for the positive active material have been formed.

[0158] The metal solution, ammonium cation complex forming agent, and basic compound introduced during the particle growth stage are the same as those used during the nucleation stage.

[0159] In the particle growth step, the metal solution may be supplied at a first flow rate and then at a second flow rate higher than the first flow rate. Specifically, the second flow rate may be 1.5 to 2.5 times, 1.6 to 2.1 times, or 1.7 to 1.8 times the first flow rate. When the metal solution is supplied by changing the flow rate from the first to the second as described above, productivity can be improved while securing sufficient reaction time to ensure that the internal structure of the particles has a pore size within an appropriate range. These internal pores can aid in crystal growth, thereby allowing for control of particle uniformity. Accordingly, reactivity with the lithium raw material during high-temperature sintering can be improved to form a stable crystal structure, and defects and strain within the crystal structure can be suppressed.

[0160] The first flow rate may be 0.1 L / h to 1 L / h, 0.15 L / h to 0.8 L / h, 0.2 L / h to 0.6 L / h, or 0.3 L / h to 0.5 L / h. When the above range is satisfied, sufficient reaction time can be secured while improving productivity, allowing particles to grow uniformly, and thus the particle size distribution of the precursor for the cathode active material can be uniform.

[0161] In the particle growth step, the metal solution may be supplied at a first flow rate for 5 hours or less, 1 hour to 4.5 hours, 2 hours to 4 hours, or 2.5 hours to 3.5 hours. When the above range is satisfied, sufficient reaction time can be secured while improving productivity, allowing the particles to grow uniformly, and thus the particle size distribution of the precursor for the cathode active material can be uniform.

[0162] The second flow rate may be 0.1 L / h to 1.1 L / h, 0.4 L / h to 1.0 L / h, 0.5 L / h to 0.9 L / h, 0.6 L / h to 0.8 L / h, or 0.65 L / h to 0.75 L / h. When the above range is satisfied, the second flow rate is higher than the first flow rate, so productivity can be secured, and at the same time, the reaction can proceed sufficiently, so particle size uniformity can be improved.

[0163] In the particle growth step, the metal solution may be supplied at a second flow rate for 5 to 40 hours, 15 to 35 hours, 20 to 32 hours, 25 to 30 hours, or 26 to 28 hours. If the above range is satisfied, sufficient reaction time is secured, so that particle size uniformity is increased and sphericity can be increased.

[0164] In the particle growth step above, the product of the second flow rate (unit: L / h) and the supply time of the second flow rate (unit: hours) may be 17.6L or more, 17.8L or more, 18L or more, 18.2L or more, 18.4L or more, 18.6L or more, 20L or less, 19.8L or less, 19.6L or less, 19.4L or less, 19.2L or less, 19L or less, 18.8L or less, or 18.6L or less. For example, in the particle growth step above, the product of the second flow rate (unit: L / h) and the supply time of the second flow rate (unit: hours) may be 17.6L or more, 18L to 20L, 18.2L to 19L, or 18.4L to 18.8L. If the above range is satisfied, the precursor particles can grow sufficiently, ensuring particle size uniformity and excellent productivity.

[0165]

[0166] The above particle growth step can be performed in an oxidizing atmosphere. In this case, the particle growth rate can be relatively delayed, which may extend the reaction time; consequently, the particles grow uniformly, resulting in a reduced span value and increased sphericity. Additionally, the degree of pores within the particles can be controlled, thereby allowing for the control of the pore area ratio of the precursor for the cathode active material.

[0167] The above oxidizing atmosphere can be formed by introducing an oxygen-containing gas in an amount such that the oxygen content per 1 kg of metal in the metal solution is 30 L to 50 L, 32 L / kg to 48 L / kg, 35 L / kg to 45 L / kg, or 38 L / kg to 42 L / kg. When the above range is satisfied, the growth rate of primary particles can also be controlled while improving particle uniformity, which can influence the formation of internal pores. Accordingly, the SPAN value, sphericity, and pore area ratio of the precursor can be formed to be appropriate.

[0168] The above oxygen-containing gas may be a gas with an oxygen content of 21% or more, such as the atmosphere, for example, or a gas with an oxygen content of 25% or more.

[0169]

[0170] In the particle growth step, the pH of the reaction solution is 10.5 to 12.5, 10.7 to 12.3, 11.0 to 12.0, or 11.2 to 11.8. When the pH of the reaction solution satisfies the above range, particle growth can proceed smoothly, allowing the primary particle size to be controlled and the crystal growth rate of the precursor to be adjusted to an appropriate range. Accordingly, this can contribute to the growth of a precursor in a uniform form.

[0171] In the particle growth step, the stirring speed of the reaction solution may be 100 rpm to 500 rpm, 200 rpm to 400 rpm, or 250 rpm to 350 rpm. When the above range is satisfied, the particle size distribution of the grown precursor may be uniform and the shape may be uniform.

[0172] In the particle growth step above, the co-precipitation reaction can be carried out at a temperature of 40°C to 80°C, 45°C to 80°C, or 45°C to 75°C. If the temperature of the co-precipitation reaction satisfies the above range, particle growth can be carried out smoothly.

[0173] In the particle growth step above, the co-precipitation reaction for growing precursor particles for the cathode active material may be performed for 3 to 100 hours, 5 to 80 hours, 10 to 50 hours, 20 to 40 hours, or 25 to 35 hours. When the above range is satisfied, the precursor particles for the cathode active material can be grown to an appropriate size, and the precursor particles can be grown with a uniform particle size distribution and shape, thereby reducing particle defects and strain during calcination.

[0174]

[0175] When the average particle size of the precursor particles in the reaction solution reaches the desired particle size, the reaction is terminated, the precursor is separated from the reaction solution through filtration or the like, and then washing and drying are performed to obtain a precursor for the cathode active material.

[0176]

[0177] According to the above method, a precursor for an anode active material as described above can be manufactured.

[0178] Specifically, the grown precursor for the positive electrode active material comprises a nickel-based hydroxide containing 50 mol% or more of nickel among the total metals. Specifically, the precursor for the positive electrode active material may comprise a nickel-based hydroxide containing 50 mol% or more, 52 mol% or more, 54 mol% or more, 55 mol% or more, 56 mol% or more, 58 mol% or more, 60 mol% or more, 80 mol% or less, 75 mol% or less, 70 mol% or less, 65 mol% or less, or 60 mol% or less of nickel among the total metals. For example, the precursor for the positive electrode active material may comprise a nickel-based hydroxide containing 50 mol% or more, 50 mol% to 80 mol%, 50 mol% to 70 mol%, or 55 mol% to 65 mol% of nickel among the total metals. If the above range is satisfied, a positive electrode active material with high energy density can be manufactured, which can result in excellent battery capacity characteristics and reduce electrolyte side reactions and gas generation.

[0179] The grown precursor for the cathode active material has a pore area ratio (PAR) of 5% to 10%. Specifically, the precursor for the cathode active material may have a pore area ratio of 5% or more, 5.5% or more, 6% or more, 6.5% or more, 7% or more, 7.5% or more, 10% or less, 9.5% or less, 9% or less, 8.5% or less, 8% or less, or 7.6% or less. For example, the precursor for the cathode active material may have a pore area ratio of 5% to 10%, 6% to 9%, 6.5% to 8.5%, or 7% to 8%. If the above pore area ratio is too low, the lack of pores prevents easy reaction with lithium, resulting in inferior particle size. If the above pore area ratio is too high, the particle size increases too much, hindering the movement of lithium ions during charging and discharging, which increases the resistance growth rate and may lead to inferior lifespan characteristics. Therefore, if the above range is satisfied, internal pores can aid in crystal growth during high-temperature sintering. Consequently, particle uniformity can be controlled, reactivity with lithium raw materials during high-temperature sintering can be improved to form a stable crystal structure, and defects and strain within the crystal structure can be suppressed. As a result, the resistance and lifespan characteristics of the cathode and battery using the manufactured cathode active material can be improved.

[0180] The grown precursor for the cathode active material has a SPAN value defined by Formula 1 below of 0.58 or less. Specifically, the precursor for the cathode active material may have a SPAN value defined by Formula 1 below of 0.58 or less, 0.56 or less, 0.54 or less, 0.52 or less, 0.5 or less, 0.48 or less, 0.1 or more, 0.15 or more, 0.2 or more, 0.25 or more, 0.3 or more, 0.35 or more, 0.4 or more, or 0.45 or more. For example, the precursor for the cathode active material may have a SPAN value defined by Formula 1 below of 0.58 or less, 0.1 to 0.58, 0.2 to 0.56, 0.3 to 0.54, 0.4 to 0.52, or 0.45 to 0.5. When the span value of the precursor for the positive electrode active material satisfies the above range, the uniform particle size distribution of the precursor allows for uniform sintering with lithium, and as a result, the effect of reducing defects and strain within the structure of the positive electrode active material occurs.

[0181] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0182] The grown precursor for the positive electrode active material has a sphericity of 0.8 or higher. Specifically, the precursor for the positive electrode active material may have a sphericity of 0.8 or higher, 0.81 or higher, 0.82 or higher, 0.83 or higher, 0.84 or higher, 0.85 or higher, 0.86 or higher, 0.87 or higher, 0.88 or higher, 0.89 or higher, 0.9 or higher, 0.91 or higher, 0.92 or higher, 0.93 or higher, 0.94 or higher, 0.95 or higher, less than 1, 0.99 or lower, 0.98 or lower, 0.97 or lower, or 0.95 or lower. For example, the precursor for the positive electrode active material may have a sphericity of 0.8 or higher, 0.81 or higher, 0.82 or higher, 0.83 to 0.99, or 0.83 to 0.98. When the above range is satisfied, heat can be transferred uniformly when the precursor for the positive electrode active material is sintered at high temperature, and stress is evenly distributed throughout the particles, so that particle uniformity can be controlled during high-temperature sintering, so that crystal growth is performed stably and the occurrence of defects or strain can be reduced.

[0183]

[0184] The above-mentioned grown precursor particles for the positive electrode active material are identical to the aforementioned precursor for the positive electrode active material, so a detailed description is omitted.

[0185]

[0186] positive electrode active material

[0187] The positive electrode active material according to the present invention comprises a lithium nickel-based oxide containing 50 mol% or more of nickel among all metals excluding lithium. Specifically, the positive electrode active material may comprise a lithium nickel-based oxide containing 50 mol% or more, 52 mol% or more, 54 mol% or more, 55 mol% or more, 56 mol% or more, 58 mol% or more, 60 mol% or more, 80 mol% or less, 75 mol% or less, 70 mol% or less, 65 mol% or less, or 60 mol% or less of nickel among all metals excluding lithium. For example, the positive electrode active material may comprise a lithium nickel-based oxide containing 50 mol% or more, 50 mol% to 80 mol%, 50 mol% to 70 mol%, or 55 mol% to 65 mol% of nickel among all metals excluding lithium. When the above ranges are satisfied, the energy density of the positive electrode active material is high, so the capacity characteristics of the battery may be excellent, and the amount of electrolyte side reactions and gas generation may be reduced.

[0188]

[0189] The above-mentioned positive electrode active material may include a lithium nickel-based oxide represented by the following chemical formula 2. In this case, the positive electrode active material may have excellent energy density, capacity characteristics, and structural stability.

[0190] [Chemical Formula 2]

[0191] Li 1+a1 [Ni x2 Co y2 M 3 z2 M 4 w2 ]O2

[0192] In the above chemical formula 2, M 3 can be Mn, Al, or a combination thereof. The above M 3 If included, the structural stability of the lithium nickel-based oxide can be improved.

[0193] In the above chemical formula 2, M 4... may be one or more doping elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, or may be one or more doping elements selected from the group consisting of W, Y, Ba, Ca, Ti, Mg, Ta, and Nb. 4 It may be optionally included in or not included in the lithium nickel-based oxide represented by the above chemical formula 2, and if included, it may play a role in facilitating calcination or improving structural stability.

[0194] In the above chemical formula 2, 1+a1 may represent the molar ratio of lithium (Li) in the lithium nickel-based oxide, and may be 1.0≤1+a1≤1.5, 1.0≤1+a1≤1.2, 1.0≤1+a1≤1.1, or 1.0≤1+a1≤1.05. When the above range is satisfied, the positive electrode active material can form a stable layered crystal structure.

[0195] In the above chemical formula 2, x2 represents the molar ratio of nickel among the total metals excluding lithium in the lithium nickel-based oxide particles, and may be 0.50≤x2<1.0, 0.50≤x2≤0.80, 0.50≤x2≤0.70, or 0.55≤x2≤0.65. When the above range is satisfied, the capacity characteristics of the positive electrode active material may be excellent.

[0196] In the above Chemical Formula 2, y2 represents the molar ratio of cobalt among the total metals excluding lithium in the lithium nickel-based oxide particles, where 0 <y2≤0.3, 0<y2≤0.2, 0<y2≤0.15, 또는 0.05≤y2≤0.12일 수 있다. 상기 범위를 만족하는 경우, 비용적인 이점을 가지면서, 출력 특성이 개선될 수 있다.

[0197] In the above chemical formula 2, z2 is M among the total metals excluding lithium in the lithium nickel-based oxide particles.3 It refers to the molar ratio of, 0 <z2≤0.4, 0<z2≤0.37, 0.1≤z2≤0.35, 0.2≤z2≤0.33 또는 0.25≤z2≤0.32일 수 있다. 상기 범위를 만족하는 경우, 양극 활물질의 구조적 안정성이 개선될 수 있다.

[0198] In the above chemical formula 2, w2 is M among the total metals excluding lithium in the lithium nickel-based oxide particles. 4 It refers to the molar ratio, which may be 0≤w2≤0.1, 0≤w2≤0.08, 0≤w2≤0.05, or 0≤w2≤0.01. When the above range is satisfied, it can play a role in promoting particle growth during calcination of the anode active material or improving crystal structure stability.

[0199]

[0200] The above-mentioned positive electrode active material may include a lithium nickel-based oxide containing nickel, cobalt, and manganese. For example, the above-mentioned positive electrode active material may include a lithium nickel-based oxide represented by the following chemical formula 2-1. When the above-mentioned lithium nickel-based oxide includes manganese, structural stability may be improved as the manganese contributes to maintaining the layered structure of the lithium nickel-based oxide.

[0201]

[0202] [Chemical Formula 2-1]

[0203] Li 1+a2 [Ni x3 Co y3 Mn z3 M 4 w3 ]O2

[0204] In the above chemical formula 2-1, M 4... may be one or more doping elements selected from the group consisting of Al, W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, or may be one or more doping elements selected from the group consisting of Al, W, Y, Ba, Ca, Ti, Mg, Ta, and Nb. 4 It may be optionally included in or not included in the lithium nickel-based oxide represented by the above chemical formula 2-1, and if included, it may play a role in facilitating sintering or improving structural stability.

[0205] In the above chemical formula 2-1, 1+a2 may represent the molar ratio of lithium (Li) in the lithium nickel-based oxide, and may be 1.0≤1+a2≤1.5, 1.0≤1+a2≤1.2, 1.0≤1+a2≤1.1, or 1.0≤1+a2≤1.05. When the above range is satisfied, the positive electrode active material can form a stable layered crystal structure.

[0206] In the above chemical formula 2-1, x2 represents the molar ratio of nickel among the total metals excluding lithium in the lithium nickel-based oxide particles, and may be 0.50≤x3<1.0, 0.50≤x3≤0.80, 0.50≤x3≤0.70, or 0.55≤x3≤0.65. When the above range is satisfied, the capacity characteristics of the positive electrode active material may be excellent.

[0207] In the above Chemical Formula 2-1, y3 represents the molar ratio of cobalt among the total metals excluding lithium in the lithium nickel-based oxide particles, where 0 <y3≤0.3, 0<y3≤0.2, 0<y3≤0.15, 또는 0.05≤y3≤0.12일 수 있다. 상기 범위를 만족하는 경우, 비용적인 이점을 가지면서, 출력 특성이 개선될 수 있다.

[0208] In the above Chemical Formula 2-1, z3 represents the molar ratio of manganese among the total metals excluding lithium in the lithium nickel-based oxide particles, where 0 <z3≤0.4, 0<z3≤0.37, 0.1≤z3≤0.35, 0.2≤z3≤0.33 또는 0.25≤z3≤0.32일 수 있다. 상기 범위를 만족하는 경우, 양극 활물질의 구조적 안정성이 개선될 수 있다.

[0209] In the above chemical formula 2-1, w3 is M among the total metals excluding lithium in the lithium nickel-based oxide particles. 4 It refers to the molar ratio of 0≤w3≤0.1, 0≤w3≤0.08, 0≤w3≤0.05, or 0≤w3≤0.01. When the above range is satisfied, it can play a role in promoting particle growth during calcination of the anode active material or improving crystal structure stability.

[0210]

[0211] In the above formula 2 or formula 2-1, the x2 / y2 or x3 / y3 may be 3.2 or more, 3.4 or more, 3.5 or more, 3.6 or more, 3.8 or more, 4.0 or more, 4.2 or more, 4.4 or more, 4.6 or more, 4.8 or more, 5.0 or more, 5.2 or more, 5.4 or more, 5.6 or more, 5.8 or more, 6.0 or more, 9.0 or less, 8.8 or less, 8.6 or less, 8.5 or less, 8.4 or less, 8.2 or less, 8.0 or less, 7.8 or less, 7.6 or less, 7.5 or less, 7.4 or less, 7.2 or less, 7.0 or less, 6.8 or less, 6.6 or less, 6.4 or less, 6.2 or less, or 6.0 or less. For example, the above x2 / y2 or x3 / y3 may be 3.2 to 9.0, 3.5 to 8.5, 4.0 to 8.0, 4.5 to 7.5, 5.0 to 7.0, or 5.5 to 6.5. When the above range is satisfied, the cathode active material can achieve a high capacity by including a high content of nickel (Ni), and the crystal structure of the cathode may not collapse after the high capacity is achieved, so the lifespan characteristics are excellent.

[0212] In the above formula 2 or formula 2-1, the x2 / z2 or x3 / z3 may be 1.0 or more, 1.1 or more, 1.2 or more, 1.3 or more, 1.4 or more, 1.5 or more, 1.6 or more, 1.7 or more, 1.8 or more, 1.9 or more, 2.0 or more, 2.8 or less, 2.7 or less, 2.6 or less, 2.5 or less, 2.4 or less, 2.3 or less, 2.2 or less, 2.1 or less, or 2.0 or less. For example, the x2 / z2 or x3 / z3 may be 1.0 to 2.8, 1.2 to 2.6, 1.4 to 2.5, 1.6 to 2.4, 1.8 to 2.2, or 1.9 to 2.1. When the above range is satisfied, variability in the c-axis direction within the layered structure during charging and discharging is suppressed by manganese (Mn), and at the same time, stable capacity development by nickel (Ni) is possible, so the electrochemical characteristics of the battery can be excellent.

[0213] In the above formula 2 or formula 2-1, the z2 / y2 or z3 / y3 is 1.5 or more, 1.6 or more, 1.7 or more, 1.8 or more, 1.9 or more, 2.0 or more, 2.1 or more, 2.2 or more, 2.3 or more, 2.4 or more, 2.5 or more, 2.6 or more, 2.7 or more, 2.8 or more, 2.9 or more, 3.0 or more, 5.0 or less, 4.9 or less, 4.8 or less, 4.7 or less, 4.6 or less, 4.5 or less, 4.4 or less, 4.3 or less, 4.2 or less, 4.1 or less, 4.0 or less, 3.9 or less, 3.8 or less, 3.7 or less, 3.6 or less, 3.5 or less, 3.4 or less, 3.3 or less, 3.2 or less, 3.1 or less, or It may be 3.0 or less. For example, the z2 / y2 or z3 / y3 may be 1.5 to 5.0, 1.7 to 4.5, 2.0 to 4.0, 2.2 to 3.8, 2.5 to 3.5, 2.7 to 3.3, or 2.9 to 3.1. When the above range is satisfied, the manganese content can be increased relatively compared to cobalt, so the structural stability of the cathode active material is excellent, so it can have excellent stability at high temperature and high voltage, and can have cost advantages.

[0214]

[0215] The above lithium nickel-based oxide is a single-particle type.

[0216] In the case of lithium nickel-based oxides in the form of single particles, compared to lithium nickel-based oxides in the form of secondary particles, there is less particle breakage due to rolling during cathode manufacturing and excellent structural stability under high temperature and / or high voltage conditions. Therefore, when single-particle lithium nickel-based oxides are applied, cathode degradation is reduced under high temperature and high voltage conditions, and there is less generation of fine particles after cathode manufacturing, resulting in less gas generation due to side reactions between fine particles and the electrolyte. Thus, when lithium nickel-based oxides in the form of single particles are applied, it is advantageous for manufacturing lithium secondary batteries with long life characteristics.

[0217] Meanwhile, the lithium nickel-based oxide, which is a single-particle type, may contain 30 or fewer, 20 or fewer, 1 to 20, or 1 to 15 nodules. If the above range is satisfied, particle breakage can be prevented and internal cracks can be reduced during electrode manufacturing, so that high-temperature life and high-temperature storage characteristics can be excellent.

[0218] Meanwhile, the average particle size of the nodules may be 0.8㎛ to 4.0㎛, 0.8㎛ to 3㎛, or 1.0㎛ to 3.0㎛. When the average particle size of the nodules satisfies the above range, particle breakage is minimized during electrode manufacturing, and the increase in resistance can be suppressed more effectively. At this time, the average particle size of the nodules refers to a value obtained by measuring the particle sizes of the nodules observed in the SEM image obtained by analyzing the positive electrode active material powder with a scanning electron microscope, and then calculating the arithmetic mean of the measured values.

[0219] Meanwhile, the above-mentioned positive active material has an average particle size D 50 This can be 2㎛ to 6㎛, 2.5㎛ to 5㎛, 3㎛ to 4.5㎛, or 3.2㎛ to 4㎛. When the above range is satisfied, the processability during electrode manufacturing is excellent, and the balance of the effects of improving electrolyte impregnation, resistance characteristics, and output characteristics can be achieved.

[0220]

[0221] The above-mentioned positive active material may have a span value defined by Formula 1 below of 0.5 to 2.5, 0.7 to 2.0, 1.0 to 1.5, 1.2 to 1.3, or 1.22 to 1.28. When the above range is satisfied, the particle distribution in the positive electrode containing the positive active material may be uniform, and accordingly, the structural stability of the positive active material at high temperature and high voltage may be improved. In addition, the impregnation of the electrolyte within the positive electrode may be improved.

[0222] [Equation 1] SPAN = (D 90 -D 10 ) / D50

[0223]

[0224] D of the above positive active material 90 It may be 5㎛ to 8㎛, 5.5㎛ to 7.5㎛, or 6㎛ to 7㎛.

[0225] D of the above positive active material 10 It may be 0.5㎛ to 3㎛, 0.7㎛ to 2.5㎛, or 1㎛ to 2㎛.

[0226]

[0227] The above positive active material has a degree of sphericity of 0.3 to 1, 0.4 to 0.99, 0.5 to 0.98, or 0.6 to 0.98. When the above range is satisfied, the shape of the positive active material particles is close to a uniform sphere, so the occurrence of internal defects or strain in the particles during charging and discharging can be reduced.

[0228]

[0229] The fine particle generation rate of the above-mentioned positive active material may be 3.0 volume% or less, 2.5 volume% or less, or 2.0 volume% or less. If the above range is satisfied, particle breakage occurring in the positive active material during rolling can be minimized.

[0230] The degree of single particle size of the above-mentioned positive active material may be 2.8 or higher, 2.8 to 4.0, 2.9 to 3.4, 3.0 to 3.3, or 3.1 to 3.2. When the above range is satisfied, particle breakage during rolling can be reduced and high-temperature durability can be improved.

[0231] The above-mentioned positive active material may have a nickel disorder (Ni-disorder) of greater than 0% and less than 5%, 1% to 4%, or 1% to 3%. When the above range is satisfied, the structural stability of the positive active material is secured, the resistance is reduced, and the lifespan degradation can be mitigated.

[0232] The above positive active material may have a strain of 0.03 or less, 0.025 or less, 0.02 or less, or 0.019 or less. When the above range is satisfied, the structural stability of the positive active material is secured, the resistance is reduced, and the lifespan degradation can be mitigated.

[0233] The above-described positive active material comprises a calcined mixture of the aforementioned precursor for the positive active material and a lithium raw material. That is, the above-described positive active material may be manufactured by mixing the aforementioned precursor for the positive active material and a lithium raw material and calcining them. Accordingly, a positive active material comprising single-particle type particles with a uniform particle size distribution and improved resistance characteristics can be manufactured.

[0234] Except for using precursor particles for the positive electrode active material obtained as described above, the calcined body of the mixture of the positive electrode active material precursor and the lithium raw material may be obtained by a calcination method known in the relevant technical field, and the method is not particularly limited.

[0235] The above lithium raw materials may include lithium-containing carbonates (e.g., lithium carbonate, etc.), hydrates (e.g., lithium hydroxide hydrate (LiOH·H2O), etc.), hydroxides (e.g., lithium hydroxide, etc.), nitrates (e.g., lithium nitrate (LiNO3), etc.), chlorides (e.g., lithium chloride (LiCl), etc.), and one of these alone or a mixture of two or more may be used.

[0236] The mixing of the precursor particles for the positive electrode active material and the lithium raw material can be carried out by solid-state mixing such as jet milling. The mixing ratio of the precursor particles for the positive electrode active material and the lithium raw material can be determined within a range that satisfies the mole fraction of each component in the positive electrode active material finally manufactured. More specifically, the precursor particles for the positive electrode active material and the lithium raw material may be mixed such that the lithium element in the precursor particles for the positive electrode active material and the lithium raw material is in a molar ratio of 1:1.0 to 1:1.5 or 1:1.0 to 1:1.3.

[0237] Although not essential, in addition to the precursor for the cathode active material and the lithium raw material, raw materials for doping some of the transition metals and / or oxygen of the cathode active material may be additionally included in the above mixture. For example, the raw material containing the doping element described above may be additionally mixed in the above mixture.

[0238]

[0239] The above calcination can be performed at a temperature of 600°C to 1,100°C, 650°C to 1,000°C, 700°C to 950°C, or 720°C to 900°C. When calcining at a temperature within the above range, the layered structure of the manufactured positive active material can be smoothly formed, and the positive active material can be formed into single-particle particles.

[0240] The above calcination may be performed for 5 to 20 hours, 7 to 15 hours, or 8 to 10 hours, but is not limited thereto. If the above range is satisfied, the positive active material can be manufactured to have a single-particle form.

[0241]

[0242] anode

[0243] The anode according to the present invention comprises the aforementioned anode active material. Specifically, the anode may comprise an anode active material layer comprising the aforementioned anode active material, and more specifically, may comprise an anode current collector; and an anode active material layer located on the anode current collector and comprising the aforementioned anode active material.

[0244]

[0245] Hereinafter, each component of the anode according to the present invention will be described in detail.

[0246]

[0247] (1) Positive current collector

[0248] Various positive current collectors used in the relevant technical field may be used as the positive current collector. For example, the positive current collector may be stainless steel, aluminum, nickel, titanium, calcined carbon, or aluminum or stainless steel surface treated with carbon, nickel, titanium, silver, etc. The positive current collector may typically have a thickness of 3 to 500 μm, and fine irregularities may be formed on the surface of the positive current collector to increase the adhesion of the positive active material. The positive current collector may be used in various forms, such as a film, sheet, foil, net, porous body, foam, nonwoven fabric, etc.

[0249]

[0250] (2) Positive active material layer

[0251] The positive active material layer may be located on the positive current collector, and specifically, may be located on one or both sides of the positive current collector. The positive active material layer may be a single layer or a multilayer structure of two or more layers.

[0252] The above positive active material layer may include a positive active material, a positive conductive material, and a positive binder.

[0253] Since the above-mentioned positive active material is identical to the positive active material according to the present invention described above, the specific characteristics of the above-mentioned positive active material are identical to those described above.

[0254]

[0255] The above positive active material may be included in an amount of 90% to 99% by weight, 92% to 98% by weight, or 94% to 97% by weight based on the total weight of the positive active material layer. If the above range is satisfied, the energy density and capacity characteristics of the lithium secondary battery to which the positive material is applied can be improved.

[0256] The above-mentioned positive electrode conductive material is used to impart conductivity to the electrode, and in the battery being constructed, it may be used without special limitations as long as it possesses electronic conductivity without causing chemical changes. Specific examples include graphite such as natural graphite or artificial graphite; carbon-based materials such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, thermal black, carbon fiber, carbon nanotube; metal powder or metal fiber such as copper, nickel, aluminum, or silver; conductive whiskers such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; or conductive polymers such as polyphenylene derivatives, and one of these alone or a mixture of two or more may be used. The above-mentioned positive electrode conductive material may typically be included in an amount of 0.1 to 10 weight%, 0.5 to 8 weight%, 0.8 to 5 weight%, or 1 to 3 weight% based on the total weight of the positive electrode active material layer.

[0257] The above-mentioned anode binder serves to improve adhesion between anode active material particles and adhesion between the anode active material and the anode current collector. Specific examples include fluoropolymer-based binders comprising polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE); rubber-based binders comprising styrene butadiene rubber (SBR), acrylonitrile-butadiene rubber, or styrene-isoprene rubber; cellulose-based binders comprising carboxyl methyl cellulose (CMC), starch, hydroxypropyl cellulose, or regenerated cellulose; polyalcohol-based binders comprising polyvinyl alcohol; polyolefin-based binders comprising polyethylene or polypropylene; polyimide-based binders; and polyester-based binders. Examples include silane-based binders, and one of these alone or a mixture of two or more may be used. The anode binder may be included in an amount of 0.1% to 10% by weight, 0.5% to 10% by weight, or 1% to 5% by weight based on the total weight of the anode active material layer.

[0258]

[0259] The anode may be manufactured by methods known in the art. For example, the anode may be manufactured by mixing an anode active material, an anode binder, and an anode conductive material in a solvent to prepare an anode slurry, applying the anode slurry onto an anode current collector, and then drying and rolling, or by casting the anode slurry onto a separate support and then laminating the film obtained by peeling it off from the support onto an anode current collector. In this case, the solvent for the anode slurry may be any anode slurry solvents generally used in the art, such as dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, water, or a mixture thereof, but is not limited thereto. The solvent may be used in an amount that dissolves or disperses the anode active material, the anode conductive material, and the anode binder, and has a viscosity such that the anode slurry can be uniformly coated.

[0260]

[0261] lithium secondary battery

[0262] A lithium secondary battery according to the present invention is described. The lithium secondary battery according to the present invention comprises a positive electrode according to the present invention; a negative electrode disposed opposite to the positive electrode; and an electrolyte. Optionally, the lithium secondary battery according to the present invention may further comprise a separator interposed between the positive electrode and the negative electrode.

[0263] Since the anode above is the same as described above, the remaining components excluding the anode will be described below.

[0264]

[0265] (1) Cathode

[0266] In a lithium secondary battery according to the present invention, the negative electrode comprises a negative electrode active material layer including a negative electrode active material, and specifically, may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector.

[0267]

[0268] The above-mentioned negative current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery, and for example, copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel surface-treated with carbon, nickel, titanium, silver, etc., and aluminum-cadmium alloy may be used. In addition, the above-mentioned negative current collector may have a thickness of 3㎛ to 500㎛, 5㎛ to 400㎛, or 8㎛ to 300㎛, and, similar to the positive current collector, fine irregularities may be formed on the surface of the current collector to strengthen the bonding force of the negative active material. For example, it may be used in various forms such as a film, sheet, foil, net, porous body, foam, nonwoven fabric, etc.

[0269]

[0270] The above negative electrode active material layer may be located on the negative electrode current collector, and specifically, may be located on one or both sides of the negative electrode current collector. The above negative electrode active material layer may have a single-layer structure or a multi-layer structure of two or more layers.

[0271] When the negative electrode active material layer is a multilayer structure composed of two or more layers, the types and / or contents of the negative electrode active material, negative electrode binder, and / or negative electrode conductive material in each layer may differ from one another. By forming the negative electrode active material layer into a multilayer structure and varying the composition of each layer, the performance characteristics of the battery, such as rapid charging performance and output characteristics, can be appropriately controlled.

[0272] As the above-mentioned negative electrode active material, a compound capable of reversible intercalation and deintercalation of lithium may be used. Specific examples include carbonaceous materials such as artificial graphite, natural graphite, graphitized carbon fiber, and amorphous carbon; metallic compounds capable of alloying with lithium, such as Si, Al, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd, Si alloys, Sn alloys, or Al alloys; and SiO₂ β Examples include metal oxides capable of doping and dedoping lithium, such as (0 < β < 2), SnO2, vanadium oxide, and lithium vanadium oxide; or composites comprising the metal compound and carbonaceous material, such as Si-C composites or Sn-C composites, and any one or more of these may be used.

[0273] The above carbonaceous materials may include both low-crystallinity carbon and high-crystallinity carbon. Representative examples of low-crystallinity carbon include soft carbon and hard carbon, while representative examples of high-crystallinity carbon include amorphous, plate-like, flake-like, spherical, or fibrous natural or artificial graphite, Kish graphite, pyrolytic carbon, mesophase pitch-based carbon fiber, meso-carbon microbeads, mesophase pitches, and high-temperature calcined carbon such as petroleum or coal tar pitch-derived cokes.

[0274] Preferably, the cathode active material may be a carbon-based cathode active material, wherein the carbon-based cathode active material may include, for example, natural graphite, artificial graphite, graphitized carbon fiber, amorphous carbon, soft carbon, hard carbon, or a combination thereof. More preferably, the carbon-based cathode active material may include natural graphite and artificial graphite.

[0275] The above carbon-based negative electrode active material has an average particle size D 50 This can be 2㎛ to 30㎛, preferably 5㎛ to 30㎛.

[0276] The above-mentioned negative electrode active material may be included in an amount of 80% to 98% by weight, 90% to 98% by weight, or 93% to 98% by weight based on the total weight of the negative electrode active material layer. When the content of the negative electrode active material satisfies the above range, excellent energy density can be achieved.

[0277]

[0278] The above cathode active material layer may further include a cathode conductive material and / or a cathode binder together with the cathode active material.

[0279] The cathode conductive material is used to impart conductivity to the cathode, and in the battery being constructed, it can be used without special restrictions as long as it has electronic conductivity without causing chemical changes. Specific examples include carbon-based materials such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, thermal black, carbon fiber, carbon nanotube; metal powders or metal fibers such as copper, nickel, aluminum, and silver; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; or conductive polymers such as polyphenylene derivatives, and one of these alone or a mixture of two or more of them may be used.

[0280] The above-mentioned cathode conductive material may typically be included in an amount of 0.1 to 10 weight%, preferably 0.1 to 8 weight%, and more preferably 0.1 to 5 weight% based on the total weight of the cathode active material layer.

[0281] The above-mentioned cathode binder serves to improve adhesion between cathode active material particles and adhesion between the cathode active material and the cathode current collector. Specific examples include polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinyl alcohol, polyacrylonitrile, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene monomer rubber (EPDM rubber), sulfonated-EPDM, styrene-butadiene rubber (SBR), fluororubber, or various copolymers thereof, and one of these alone or a mixture of two or more may be used.

[0282] The above-mentioned cathode binder may be included in an amount of 0.1 to 10 weight%, preferably 0.5 to 10 weight%, and more preferably 1 to 8 weight% based on the total weight of the cathode active material layer.

[0283]

[0284] The above cathode may be manufactured by methods known in the art. For example, the cathode may be manufactured by mixing a cathode active material, a cathode binder, and / or a cathode conductive material in a solvent to prepare a cathode slurry, applying the cathode slurry onto a cathode current collector, and then drying and rolling, or by casting the cathode slurry onto a separate support and then laminating the film obtained by peeling it off from the support onto a cathode current collector.

[0285] Meanwhile, solvents commonly used in the relevant technical field may be used as the solvent for the cathode slurry, for example, dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, water, or mixtures thereof, but are not limited thereto. The solvent may be used in an amount that dissolves or disperses the cathode active material, cathode conductive material, and cathode binder, and has a viscosity such that the cathode slurry can be uniformly coated.

[0286]

[0287] (2) Electrolyte

[0288] The electrolyte according to the present invention may include a lithium salt and an organic solvent.

[0289] The above lithium salt can be used without special restrictions as long as it is a compound capable of providing lithium ions used in lithium secondary batteries. Specifically, the lithium salt may be LiPF6, LiClO4, LiAsF6, LiBF4, LiSbF6, LiAlO4, LiAlCl4, LiCF3SO3, LiC4F9SO3, LiN(C2F5SO3)2, LiN(C2F5SO2)2, LiN(CF3SO2)2, LiCl, LiI, or LiB(C2O4)2. The concentration of the lithium salt is preferably used within the range of 0.1 to 5.0 M or 0.1 to 3.0 M. When the concentration of the lithium salt falls within the above range, the electrolyte has appropriate conductivity and viscosity, so it can exhibit excellent electrolyte performance and allow lithium ions to move effectively.

[0290]

[0291] The above organic solvent may include at least one of a cyclic carbonate-based organic solvent, a linear carbonate-based organic solvent, a linear ester-based organic solvent, and a cyclic ester-based organic solvent.

[0292] The above-mentioned cyclic carbonate-based organic solvent is a high-viscosity organic solvent that has a high dielectric constant and can effectively dissociate lithium salts in the electrolyte; specifically, it may be a non-fluorinated saturated cyclic carbonate-based organic solvent. The above-mentioned cyclic carbonate-based organic solvent may include at least one organic solvent selected from the group consisting of ethylene carbonate (EC), fluoroethylene carbonate (FEC), propylene carbonate (PC), 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene carbonate, and vinylene carbonate; more specifically, it may include at least one selected from the group consisting of ethylene carbonate (EC) and fluoroethylene carbonate (FEC); and even more specifically, it may include ethylene carbonate (EC).

[0293] In addition, the linear carbonate-based organic solvent is an organic solvent having low viscosity and low dielectric constant, and specifically may be a non-fluorinated linear carbonate. The linear carbonate-based solvent may include at least one selected from the group consisting of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate, ethylmethyl carbonate (EMC), methylpropyl carbonate, and ethylpropyl carbonate; more specifically, it may include at least one selected from the group consisting of ethylmethyl carbonate (EMC) and diethyl carbonate (DEC); and more specifically, it may include ethylmethyl carbonate (EMC).

[0294] Specific examples of the above linear ester-based organic solvent include at least one organic solvent selected from the group consisting of methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, and butyl propionate.

[0295] The above-mentioned cyclic ester-based organic solvent may include at least one organic solvent selected from the group consisting of butyrolactone, valerolactone, and caprolactone.

[0296] Preferably, the electrolyte according to the present invention may include ethylene carbonate and dimethyl carbonate as organic solvents.

[0297]

[0298] Meanwhile, in addition to the electrolyte components, the above electrolyte may additionally include other additives for the purpose of improving battery life characteristics, suppressing battery capacity reduction, and improving battery discharge capacity.

[0299] The above additive may include, for example, at least one additive selected from the group consisting of non-fluorinated unsaturated cyclic carbonate compounds, halogen-substituted carbonate compounds, sulfone compounds, sulfate compounds, borate compounds, nitrile compounds, benzene compounds, amine compounds, silane compounds, and lithium salt compounds different from the lithium salt included in the electrolyte.

[0300] Specifically, the additive is vinylene carbonate (VC), vinylethylene carbonate, fluoroethylene carbonate (FEC), 1,3-propane sulfone (PS), 1,4-butane sulfone, ethene sulfone, 1,3-propene sulfone (PRS), 1,4-butene sulfone, 1-methyl-1,3-propene sulfone, ethylene sulfate (ESA), trimethylene sulfate (TMS), methyl trimethylene sulfate (MTMS), tetraphenyl borate, lithium oxalyl difluoroborate, succinonitrile, adiponitrile, acetonitrile, propionitrile, butyronitrile, valeronitrile, caprylonitrile, heptanitrile, cyclopentane carbonitrile, cyclohexane carbonitrile, 2-fluorobenzonitrile, Examples include one or more compounds selected from the group consisting of 4-fluorobenzonitrile, difluorobenzonitrile, trifluorobenzonitrile, phenylacetonitrile, 2-fluorophenylacetonitrile, 4-fluorophenylacetonitrile, fluorobenzene, triethanolamine, ethylenediamine, tetravinylsilane, LiN(SO2F)2 (Lithium bis(fluorosulfonyl)imide, LiFSI), LiN(SO2CF3)2 (lithium bis(trifluoromethane sulfonyl)imide, LiTFSI), LiPO2F2, LiODFB, LiBOB (lithium bis-oxalate toborate (LiB(C2O4)2)) and LiBF4.

[0301] The above additives may be included in an amount of 0.01 to 20 weight% based on the total weight of the electrolyte, or in an amount of 0.05 to 5.0 weight%. When the above range is satisfied, the low-temperature output of the battery, high-temperature storage characteristics, and high-temperature life characteristics can be improved, side reactions within the electrolyte can be reduced, and the presence of the additives as unreacted substances can be suppressed.

[0302]

[0303] *295

[0304] (3) Separator

[0305] The above separator physically separates the negative electrode and the positive electrode and provides a pathway for the movement of lithium ions; any separator typically used in lithium secondary batteries can be used without any special restrictions. In this case, the separator may be interposed between the positive electrode and the negative electrode.

[0306] As the above separator, a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, and an ethylene / methacrylate copolymer, or a laminated structure of two or more layers thereof may be used. In addition, a conventional porous nonwoven fabric, such as a nonwoven fabric made of high-melting-point glass fibers or polyethylene terephthalate fibers, may be used. Furthermore, a coated separator containing a ceramic component or a polymer material may be used to ensure heat resistance or mechanical strength, and may optionally be used in a single-layer or multi-layer structure.

[0307]

[0308] The lithium secondary battery according to the present invention as described above can be usefully applied to portable devices such as mobile phones, laptop computers, and digital cameras, as well as electric vehicles such as hybrid electric vehicles (HEVs). Since the lithium secondary battery according to the present invention exhibits excellent thermal stability and can realize excellent capacity characteristics, it can be particularly usefully applied in the field of electric vehicles.

[0309] According to another embodiment of the present invention, a battery module comprising a lithium secondary battery according to the present invention as a unit cell and a battery pack comprising the same are provided.

[0310] The above battery module or battery pack can be used as a power source for one or more medium-to-large devices, including a power tool; an electric vehicle (EV), a hybrid electric vehicle, and a plug-in hybrid electric vehicle (PHEV); or a power storage system.

[0311]

[0312] The present invention will be explained in more detail below through specific embodiments. However, the following embodiments are intended only to enable a person skilled in the art to fully understand and easily implement the present invention, and the scope of the present invention is not limited to the following embodiments.

[0313]

[0314] Preparation Example

[0315] Preparation Example 1

[0316] (1) Nucleation stage

[0317] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0318] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0319] (2) Particle growth stage

[0320] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.5, and the precursor particles were grown by reacting while stirring at 300 rpm for 30 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.7 L / h (second flow rate) for 27 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0321] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0322]

[0323] Preparation Example 2

[0324] (1) Nucleation stage

[0325] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0326] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50 This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0327] (2) Particle growth stage

[0328] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.5, and the precursor particles were grown by reacting while stirring at 300 rpm for 29 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.7 L / h (second flow rate) for 26 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0329] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0330]

[0331] Preparation Example 3

[0332] (1) Nucleation stage

[0333] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0334] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50 This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0335] (2) Particle growth stage

[0336] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.3, and the precursor particles were grown by reacting while stirring at 300 rpm for 28 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.7 L / h (second flow rate) for 25 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0337] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0338]

[0339] Preparation Example 4

[0340] (1) Nucleation stage

[0341] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0342] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50 This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0343] (2) Particle growth stage

[0344] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.5, and the precursor particles were grown by reacting while stirring at 300 rpm for 24 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.8 L / h (second flow rate) for 21 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0345] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0346]

[0347] Preparation Example 5

[0348] (1) Nucleation stage

[0349] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0350] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50 This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0351] (2) Particle growth stage

[0352] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.5, and the precursor particles were grown by reacting while stirring at 270 rpm for 27 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.7 L / h (second flow rate) for 23 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0353] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0354]

[0355] Preparation Example 6

[0356] (1) Nucleation stage

[0357] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0358] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50 This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0359] The reaction solution in which the nucleus was formed was transferred from the first reactor to the second reactor.

[0360] (2) Particle growth stage

[0361] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.4, and the precursor particles were grown by reacting while stirring at 270 rpm for 24 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.9 L / h (second flow rate) for 21 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0362] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0363]

[0364] Preparation Example 7

[0365] (1) Nucleation stage

[0366] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0367] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50 This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0368] (2) Particle growth stage

[0369] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.7, and the precursor particles were grown by reacting while stirring at 300 rpm for 28 hours while supplying a metal solution, an aqueous NaOH solution, an aqueous NH4OH solution, and oxygen gas. At this time, the metal solution was supplied at a supply rate of 0.4 L / h (first flow rate) for 3 hours and at a supply rate of 0.7 L / h (second flow rate) for 25 hours to carry out the co-precipitation reaction. In addition, the oxygen gas was supplied such that the amount of oxygen per 1 kg of transition metal in the metal solution was 40 L.

[0370] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0371]

[0372] Preparation Example 8

[0373] (1) Nucleation stage

[0374] A metal solution with a concentration of 2.0 M was prepared by dissolving NiSO4, CoSO4, and MnSO4 in ion-exchanged water in amounts such that the molar ratio of nickel:cobalt:manganese was 60:10:30. A 10L batch reactor (first reactor) was filled with distilled water, ammonia water with a concentration of 9 wt%, and an aqueous sodium hydroxide solution with a concentration of 25 wt%, and the reactor temperature was raised while purging with N2 gas and stirring at 300 rpm.

[0375] When the temperature of the reaction solution inside the first reactor reaches 45℃, the metal solution is quantitatively injected at a supply rate of 0.4 L / h and ammonia water with a concentration of 20 wt% is injected at a rate of 0.01 L / h, and an aqueous sodium hydroxide solution is injected using a pH peristaltic pump to maintain the pH of the reaction solution at 11.95. In the nucleation stage, the reaction is carried out for approximately 5 hours, and the average particle size D of the nuclei produced 50This was performed to make the size approximately 2.0 μm. The reaction solution in which the nuclei were formed was transferred from the first reactor to the second reactor.

[0376] (2) Particle growth stage

[0377] Next, NaOH was added to the reaction solution in which the precursor nuclei for the anode active material were formed in the second reactor to adjust the pH to 11.5, and the precursor particles were grown by reacting under an N2 atmosphere for 11 hours while stirring at 300 rpm while supplying the metal solution, NaOH aqueous solution, and NH4OH aqueous solution. At this time, the co-precipitation reaction was carried out by supplying the metal solution at a rate of 0.7 L / h.

[0378] After the reaction was completed, the reaction solution was filtered and dried to obtain the precursor powder.

[0379]

[0380] Experimental Example 1: Evaluation of Characteristics of Precursor for Anode Active Material

[0381] Sphericity of the precursor for the cathode active material prepared in the above Preparation Examples 1 to 8, D 50 The SPAN value and pore area ratio (PAR) were measured using the following method. The results are shown in Table 1 below.

[0382]

[0383] (1) Sphericity

[0384] Using scanning electron microscope (SEM) images obtained from the precursor particles for cathode active materials prepared in Preparation Examples 1 to 8 above, the particles were converted to two dimensions, and the average values ​​of 300 particles were measured from the minimum particle diameter (Dmin, short diameter), maximum particle diameter (Dmax, long diameter), and area using an image analysis program on the converted images. Specifically, the values ​​were calculated using the following Equation A.

[0385] [Equation A] Roundness = (4 × Area) / (π × (D max ) 2)

[0386]

[0387] (2) D 50 , span value

[0388] This refers to the particle size corresponding to 50% of the volume cumulative amount of the volume cumulative particle size distribution of the precursor powder for the positive electrode active material prepared in Preparation Examples 1 to 8 above, and was measured using the laser diffraction method. Specifically, the precursor powder for the positive electrode active material prepared in Preparation Examples 1 to 8 above was dispersed in a dispersion medium, then introduced into a commercially available laser diffraction particle size measuring device (Microtrac MT 3000), irradiated with ultrasound of approximately 28 kHz at an output of 60 W, obtained a volume cumulative particle size distribution graph, and then measured by determining the particle size corresponding to 50% of the volume cumulative amount.

[0389] D, which is the particle size corresponding to 10% and 90% of the cumulative volume in the above volume cumulative particle size distribution graph. 10 , D 90 After additionally measuring, the span value defined by Equation 1 below was calculated.

[0390] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0391]

[0392] (3) Pore area ratio

[0393] Using images obtained by scanning electron microscope (SEM) of the cathode active material precursor particles prepared in Preparation Examples 1 to 8 above, the particles were converted to two dimensions, and the pore distribution analysis was performed on the two-dimensional images using an image analysis program. Specifically, the cathode active material precursors prepared in Preparation Examples 1 to 8 above were mixed with carbon black and a PVDF binder in N-methylpyrrolidone in a weight ratio of 95:2:3 to prepare a cathode slurry, and the cathode slurry was applied to one side of an aluminum current collector with a thickness of 20 μm. The applied cathode composite layer was dried at 130°C to produce an electrode, and the electrode was analyzed using the image analysis software WinRoof 6.1.1 to indicate the voids within the cathode active material precursor particles as shading and the dense parts within the precursor particles as white. The pore area ratio (PAR) was calculated by determining the ratio (%) for each of the 20 or more precursor particles among the measured positive active material precursors as [shaded area / (shaded area + white area) × 100].

[0394] Sphericity SPAN value D 50 [㎛] Pore Area Ratio (PAR) [%] Preparation Example 10.8 30.48 3.35 7.56 Preparation Example 20.8 10.47 3.30 6.62 Preparation Example 30.8 00.48 3.29 4.1 Preparation Example 40.8 10.59 3.38 7.80 Preparation Example 50.76 0.49 3.30 6.19 Preparation Example 60.76 0.60 3.30 3.85 Preparation Example 70.8 30.55 3.38 11.7 Preparation Example 80.63 1.08 3.68 8.8

[0395] Referring to Table 1 above, it can be seen that the precursors for the positive electrode active material prepared in Preparation Examples 1 and 2 satisfy a sphericity of 0.80 or higher, a SPAN value of 0.58 or lower, and a pore area ratio of 5 to 10%. On the other hand, it can be seen that the precursors for the positive electrode active material prepared in Preparation Examples 3 to 8 do not satisfy at least one of the following: a sphericity of 0.80 or higher, a SPAN value of 0.58 or lower, and a pore area ratio of 5 to 10%. In particular, the precursor for the positive electrode active material prepared in Preparation Example 8 had a very poor sphericity and severe clumping, making it impossible to manufacture the positive electrode active material.

[0396] Examples and Comparative Examples

[0397]

[0398] Example 1

[0399] The cathode active material precursor prepared in Preparation Example 1 above and LiOH were mixed such that the molar ratio of (Ni+Co+Mn) : Li was 1 : 1.05, and then calcined at 740°C for 10 hours to prepare the cathode active material. The prepared cathode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0400]

[0401] Example 2

[0402] A positive electrode active material was prepared using the precursor for the positive electrode active material prepared in Preparation Example 2 above, in the same manner as in Example 1. The prepared positive electrode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0403]

[0404] Comparative Example 1

[0405] A positive electrode active material was prepared using the precursor for the positive electrode active material prepared in Preparation Example 3 above, in the same manner as in Example 1. The prepared positive electrode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0406]

[0407] Comparative Example 2

[0408] A positive electrode active material was prepared using the precursor for the positive electrode active material prepared in Preparation Example 4 above, in the same manner as in Example 1. The prepared positive electrode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0409]

[0410] Comparative Example 3

[0411] A positive electrode active material was prepared using the precursor for the positive electrode active material prepared in Preparation Example 5 above, in the same manner as in Example 1. The prepared positive electrode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0412]

[0413] Comparative Example 4

[0414] A positive electrode active material was prepared using the precursor for the positive electrode active material prepared in Preparation Example 6 above, in the same manner as in Example 1. The prepared positive electrode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0415]

[0416] Comparative Example 5

[0417] A positive electrode active material was prepared using the precursor for the positive electrode active material prepared in Preparation Example 7 above, in the same manner as in Example 1. The prepared positive electrode active material is LiNi 0.6 Co 0.1 Mn 0.3 It was confirmed to have the composition of O2 and the form of a single particle.

[0418]

[0419] Experimental Example 2: Characterization of Cathode Active Material

[0420] D of the positive active material particles prepared in Examples 1-2 and Comparative Examples 1-5 above 50 SPAN value, pore area ratio (PAR), and single-grained degree were measured using the following methods. The results are shown in Table 2 below.

[0421]

[0422] (1) D 50 , span value

[0423] This refers to the particle size corresponding to 50% of the volume cumulative amount of the volume cumulative particle size distribution of the positive electrode active material powders prepared in Examples 1-2 and Comparative Examples 1-5, and was measured using the laser diffraction method. Specifically, the positive electrode active material powders prepared in Examples 1-5 and Comparative Examples 1-7 were dispersed in a dispersion medium, then introduced into a commercially available laser diffraction particle size measuring device (Microtrac MT 3000), irradiated with ultrasound of approximately 28 kHz at an output of 60 W, obtained a volume cumulative particle size distribution graph, and then measured by determining the particle size corresponding to 50% of the volume cumulative amount.

[0424] D, which is the particle size corresponding to 10% and 90% of the cumulative volume in the above volume cumulative particle size distribution graph. 10 , D 90 After additionally measuring, the span value defined by Equation 1 below was calculated.

[0425] [Equation 1] SPAN = (D 90 -D 10 ) / D 50

[0426]

[0427] (2) Pore area ratio

[0428] Using images obtained by scanning electron microscope (SEM) of the positive active material particles prepared in Examples 1-2 and Comparative Examples 1-5, the particles were converted to two dimensions, and the pore distribution analysis was performed on the two-dimensional images using an image analysis program. Specifically, the positive active materials prepared in Examples 1-5 and Comparative Examples 1-7 were mixed with carbon black and a PVDF binder in N-methylpyrrolidone in a weight ratio of 95:2:3 to prepare a positive slurry, and the positive slurry was applied to one side of an aluminum current collector with a thickness of 20 μm. The applied positive composite layer was dried at 130°C to produce an electrode, and the electrode was analyzed using the image analysis software WinRoof 6.1.1 to indicate the voids within the positive active material particles as shading and the dense parts within the positive active material particles as white. The pore area ratio (PAR) was determined by calculating the ratio (%) for each of the 20 or more measured positive active material particles as [shaded area / (shaded area + white area) × 100].

[0429]

[0430] (3) Single-particle magnetization

[0431] For each manufactured positive electrode active material, the value obtained from "Elector-on BackSacter Diffraction (EBSD) analysis" was substituted into the following Equation B to calculate the degree of single particle formation.

[0432] [Equation B]

[0433]

[0434] In the above equation B, R i is the unitless number of the half-diameter (unit: μm) of the i-th grain measured when the electrode cross-section is analyzed by Electron Backscatter Diffraction (EBSD) after the electrode manufactured using the target positive electrode active material powder is ion-milled, and n is the unitless number of the total number of grains measured through the EBSD analysis.

[0435]

[0436] SPAN value D 50 [㎛] Single particle size Example 11.263.513.1 Example 21.253.563.1 Comparative Example 11.273.502.4 Comparative Example 21.273.502.7 Comparative Example 31.263.542.6 Comparative Example 41.253.501.9 Comparative Example 51.33.513.5

[0437] Experimental Example 3: Evaluation of Life Characteristics

[0438] An anode slurry was prepared by mixing the anode active material prepared in Examples 1-2 and Comparative Examples 1-5, PVdF as a binder, and carbon black as a conductive material with N-methylpyrrolidone in a weight ratio of 95:3:2. The anode slurry was applied to one side of an aluminum thin film, dried at 100°C, and then rolled to produce an anode.

[0439] The cathode used lithium metal.

[0440] An electrode assembly was manufactured by interposing a porous polyethylene separator between the anode and cathode manufactured above, and the electrode assembly was placed inside a battery case and an electrolyte was injected into the case to manufacture a coin half-cell type lithium secondary battery. At this time, the electrolyte used was prepared by dissolving 1M lithium hexafluorophosphate (LiPF6) in an organic solvent mixed with ethylene carbonate (EC) and ethyl methyl carbonate (EMC) in a volume ratio of 1:2.

[0441] Each coin half-cell type lithium secondary battery manufactured above was charged to 4.4V at 45℃ with a constant current of 0.5C, and then discharged to 2.5V with a constant current of 0.1C, with 50 cycles of charge and discharge being performed.

[0442]

[0443] (1) Capacity retention rate

[0444] The capacity retention rate was calculated using the formula below, and the results are shown in Table 4 below.

[0445] - Capacity retention rate (%) = {(Discharge capacity after 50 cycles / Discharge capacity after 1 cycle)} X 100

[0446]

[0447] (2) Resistance increase rate

[0448] After one cycle of charging and discharging, the discharge capacity after one cycle was measured using an electrochemical charge / discharger, and the SOC was adjusted to 0%. Then, a pulse of 0.1C was applied for 60 seconds, and the initial resistance was calculated through the difference between the voltage before and after the pulse application.

[0449] After 50 cycles of charging and discharging, the resistance after 50 cycles was calculated using the same method as above, and the resistance increase rate was calculated using the formula below, and the results are shown in Table 4 below.

[0450] Resistance Increase Rate (%) = (Resistance after 50 cycles - Initial resistance) / Initial resistance X 100

[0451] Capacitance Retention Rate [%] Resistance Increase Rate [%] Example 1 95.7 78.9 Example 2 95.4 79.0 Comparative Example 1 94.6 80.4 Comparative Example 2 94.9 81.7 Comparative Example 3 95.1 83.8 Comparative Example 4 93.4 88.7 Comparative Example 5 94.2 82.0

[0452] Referring to Table 3 above, it can be confirmed that the cathode active materials of Examples 1 and 2, prepared using the precursors for cathode active materials prepared in Preparation Examples 1 and 2, have a higher capacity retention rate and a lower resistance increase rate than the cathode active materials of Comparative Examples 1 to 5, prepared using the precursors for cathode active materials prepared in Preparation Examples 3 to 7.

[0453] Experimental Example 4: Evaluation of Anode Active Material Strain

[0454] The strain of the positive active material was measured by analyzing the XRD data obtained from X-ray diffraction analysis of the positive active material powders prepared in Examples 1 and 2 and Comparative Examples 1 to 5 using the Rietveld refinement method. At this time, the X-ray diffraction analysis was performed using a Bruker D8 Endeavor equipped with a LynxEye XE-T-position sensitive detector (light source: Cu-Kα, λ=1.54 Å). The sample was placed in the groove of a standard powder holder, the surface was smoothed using a slide glass, and the sample was filled so that its height aligned with the edge of the holder. Measurements were then taken for the FDS 0.5°, 2θ = 15°–90° range under conditions of a step size of 0.02° and a total scan time of approximately 20 minutes. Rietveld refinement was performed on the measured data, considering the charge at each site (metals at transition metal sites were +3, and Ni at Li sites was +2) and cation mixing. Specifically, for strain analysis, the Fundamental Parameter Approach (FPA) implemented in the Bruker TOPAS program was used for instrumental broadening, and all peaks within the measurement range were used during fitting. Peak The peak shape was fitted using only the Lorenzian contribution as the First Principle (FP) among the peak types available in TOPAS.

[0455] Strain Example 10.0190 Example 20.0199 Comparative Example 10.0205 Comparative Example 20.0204 Comparative Example 30.0211 Comparative Example 40.0307 Comparative Example 50.0268

[0456] Referring to Table 4 above, it can be confirmed that the positive active material of Examples 1 and 2, prepared using the positive active material precursor prepared in Preparation Examples 1 and 2, has less strain than the positive active material of Comparative Examples 1 to 4, prepared using the positive active material precursor prepared in Preparation Examples 3 to 7.

Claims

1. A nickel-based hydroxide containing 50 mol% or more of nickel among the total metals, and The Pore Area Ratio (PAR) is 5% to 10%, and The SPAN value defined by the following Equation 1 is 0.58 or less, and A precursor for a positive electrode active material having a degree of sphericity of 0.8 or higher. [Equation 1] SPAN = (D 90 -D 10 ) / D 50 2. In Paragraph 1, Average particle size D of the above-mentioned precursor for the positive electrode active material 50 A precursor for a positive electrode active material having a thickness of 2.0㎛ to 6.0㎛.

3. In Paragraph 1, The above nickel-based hydroxide is a precursor for an anode active material containing 50 mol% to 70 mol% of nickel among the total metals.

4. In Paragraph 1, The above nickel-based hydroxide is a precursor for an anode active material represented by the following chemical formula 1. [Chemical Formula 1] Ni x0 Co y0 M 1 z0 M 2 w0 (OH)2 In the above chemical formula 1, 0.50≤x0<1.0, 0 <y0≤0.3, 0<z0≤0.4, 0≤w0≤0.1이고, M 1 is Mn, Al, or a combination thereof, and M 2 It is one or more doping elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo.

5. In Paragraph 4, In the above Chemical Formula 1, 0.50≤x0≤0.7, 0 <y0≤0.15, 0<z0≤0.3, 0≤w0≤0.1이고, 1.5≤z0 / y0≤5.0인, 양극 활물질용 전구체.

6. A calcined body comprising a mixture of a precursor for an anode active material and a lithium raw material according to any one of paragraphs 1 to 5, and It comprises a lithium nickel-based oxide containing 50 mol% or more of nickel among all metals excluding lithium, and The above lithium nickel-based oxide is a positive electrode active material in the form of single-particle particles.

7. In Paragraph 6, The above lithium nickel-based oxide is a positive electrode active material represented by the following chemical formula 2. [Chemical Formula 2] Li 1+a1 [Ni x2 Co y2 M 3 z2 M 4 w2 ]O2 In the above chemical formula 2, 1.0≤1+a1≤1.5, 0.5≤x2<1, 0 <y2<0.3, 0<z2<0.4, 0≤w2≤0.1임 M 3 is Mn, Al, or a combination thereof, and M 4 It is one or more doping elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo.

8. In Paragraph 6, In the above chemical formula 2, 0.5≤x2≤0.7, 0 <y2≤0.2, 0<z2≤0.3, 0≤w2≤0.1이고, A positive active material having 1.5≤z2 / y2≤5.

0.

9. In Paragraph 6, A positive active material having a fine generation rate of 3.0 volume% or less.

10. In Paragraph 6, The above positive active material has an average particle size D 50 A positive electrode active material having a length of 2 to 6 μm.

11. In Paragraph 6, The above positive active material is a positive active material having a SPAN value of 0.5 to 2.5 as defined by Formula 1 below. [Equation 1] SPAN = (D 90 -D 10 ) / D 50 12. In Paragraph 6, A positive active material having a single particle size of 2.8 or higher.

13. In Paragraph 6, The above positive active material is a positive active material having a nickel disorder (Ni-disorder) greater than 0% and less than 5%.

14. A positive electrode comprising a positive electrode active material according to paragraph 6.

15. A lithium secondary battery comprising: a positive electrode according to claim 14; a negative electrode disposed opposite to the positive electrode; and an electrolyte.

16. A nucleation step of preparing a reaction solution containing a precursor nucleus for an anode active material formed by supplying and reacting a metal solution containing 50 mol% or more of nickel among the total metals, an ammonium cation complex forming agent, and a basic solution in a first reactor, and transferring the reaction solution from the first reactor to a second reactor; and A particle growth step comprising growing precursor particles for a positive electrode active material by co-precipitating a reaction solution in which a precursor nucleus for a positive electrode active material is formed in the second reactor while supplying the metal solution, an ammonium cation complex forming agent, and a basic compound; A method for manufacturing a precursor for an anode active material, wherein the particle growth step is performed in an oxidizing atmosphere, and the oxidizing atmosphere is formed by introducing an oxygen-containing gas in an amount such that the oxygen content per 1 kg of transition metal in the metal solution is 30 L to 50 L.

17. In Paragraph 16, A method for manufacturing a precursor for an anode active material, wherein in the particle formation step, the metal solution is supplied at a first flow rate, and then supplied at a second flow rate that is 1.5 to 2.5 times the first flow rate.

18. In Paragraph 16, A method for manufacturing a precursor for an anode active material, wherein the pH of the reaction solution in the particle formation step is 10.5 to 12.5.

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